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Since the casting of alloy iron is usually a continuous rathc.r than a hatch process, the problem of composition caontrol rcsolvc~ itself into :L c~~~trol of the drifts in the concentration of the several alloying constituc~nts in ttlc Irloltcn iron in the furnace or cupola. If the drifts are to be maintained uithin n::rro:v limits of tolerance, the analysis system used must tncet several rtquircrnc3it~ The accuracy of the analysis must, of course, be adequate; spcrifically, the, uucortainty must be substantially less thrn t,he permissible Variation irl content. In addition, it is of vital importance that the elapsed time bctwt,cn the pouring of a sample of the iron and the posting of the analysis results should bc made as brief as possible; otherwise, a control of drifts is not provided and an inspection analysis only results. Por some years, the authors have been interested in the application of the spectrograph to routine control problems in iron and steel. Papers have been published elsewhere?,3 on the development of a spectrographic method of analysis and its installation at the plant of the Campbell, Wyant and Cannon Foundry Company, Muskegon, Michigan. The procecfurc permits thr nnalysia of a sample of cast iron for chromium, copper, manganese, molybdenum, nickel nrld silicon in seven minutes elapsed time, while the accl!rucy exceeds that, of the routine chemical wet methods previously used. In the analysis procedure, spectra arc recorded on a photographic plate on glass sufficiently thin to accept’without fracture the curvature imposed by the spectrograph. The plate is processed, and, sinrr efforts to measurr tlcnsities on wet plates have proved uniformly ullsatisfactory, it is dried hefurc: the rcadinps are taken. Since the processing and drying of the photographic, plate was in;tially, and still remains, the most protracted optbrution of thf;tualysis ~chcclulr, the problem of rcclucing the time required has bt2c.n given consitlrreblr~ attention. It is thought that the technique dcvrloprd may be of interest to GpCctrnscopists and to others for whom rapid plate progressing is urgc>nt. IM;lilq of t hlb pro4ure are prcscnted below \Vhile the processing of any photographic plate may he Il;l

The fate of basal nitrogen (ammonium sulfate) enriched with 15N was investigated in the paddy field in 1969 and 1970. The paddy soil was relatively poor in organic matter, fine-textured and poorly drained. Rice plant was transplanted at two different times and was grown with two rates of basal nitrogen addition as previouly reported. The soil ammonium nitrogen derived from the basal fertilizer was more in the plots with the high rate of basal nitrogen than in those with the low rate. It decreased gradually and almost disappeared in every experimental, plot at the end of June. The fact above-mentioned was coincident with the results of a previous paper indicating that the absorption of basal nitrogen was finished in all the experimental plots at the end of June. The quantities of fertilizer nitrogen left in the soil after harvest ranged from 18 to 21 per cent. On the other hand, 22 to 27 per cent of the nitrogen was absorbed by rice plant. Therefore, the recovery of basal nitrogen was less than 50 per cent. According to the frequent determinations of the amounts of nitrogen absorbed by rice plant and soil ammonium nitrogen, it was assumed that ammonium formation in the soil had two maxima during the growing season -one, from the early to middle June and another, from the end of July to early in August.

In the previous paper (Nishiyama, 1952c), the writer presumed that the transparent fluid constituting a part of sperm-serum of a cock might be a fluid originated in blood. This experiment was performed by using isotope P32 to test whether this presumption might be true or not.The specific activity of the transparent fluid was higher than that of blood at 10 minutes after the intravenous injection of 0.8mc. of P32. A severe decrease in specific activity of the fluid was observed for six hours after the injection, and thereafter, the grade of decrease became much slower. There seemed no temporary increase at all in the decreasing curve of the specific activity. Moreover, the decreasing curve of the secific activity of the transparent fluid resembled considerably to that of the plasma.From these evidences, the writer believes that the transparent fluid is a fluid of blood origin.

THE original cages used by us for rearing Glossina austeni were made of deal (coniferous softwood) by the local carpenter; the wood was left untreated. A precision wood-working firm was commissioned to make similar cages in large numbers. On their advice, mahogany plywood, exterior grade, was used, and the cages surface-sprayed with a melamine resin which would seal the wood against absorption of faeces and facilitate the washing of dirty boxes.

Small-signal behavior of unipolar currents injected in semiconductors or insulators is theoretically studied. The one-dimensional problem of plane-parallel electrodes is considered. Analysis neglects diffusion but takes into account carrier mobility field dependence, ionized impurities, and trapping. Arbitrary boundary conditions are assumed. The present theory describes the small-signal response by a set of four complex quantities recalling the Llewellyn-Peterson coefficients for vacuum tubes. The present paper represents a generalization of previous results obtained by Yoshimura in the following respects: new physical phenomena (hot carrier effects and trapping) are taken into account, and new applications of the derived coefficients are suggested. This paper also contains a brief comment on physical situations and devices that can be studied by the present theory, paying particular attention to high-frequency negative-resistance devices.

In view of the fact that the chemical changes taking place in the formation of vitamin D on irradiating ergosterol remain still unexplained, it was hoped to obtain some information on the nature of these changes by a study of the monomolecular surface films on water of some of the best defined fractions of the mixture of products formed. The technique employed in the measurements of the films, as described by one of us in various papers (Adam, 1926, 1; 1926, 2; 1928), consists essentially in obtaining substances in a layer, one molecule thick, on the surface of water, and measuring the area per molecule and its variation on compressing the film laterally. The simplest way of regarding the molecules in the films is as small boating objects, adhering to each other laterally by their mutual attractions, and adhering individually to the water.

The papers by Bowden, Young & Rowe and by Shooter show that the mechanism of friction of non-metals is similar to that of metals; strong adhesion occurs at the points of real contact and these regions must be sheared for sliding to take place. The reality of this strong adhesion is difficult to demonstrate directly, since, in general, the ‘junctions’ are broken by released elastic stresses as the load is removed. With a soft metal, such as indium, however, strong normal adhesive forces are readily observed (McFarlane & Tabor 1948; Parker & Hatch 1950). It is interesting to compare the frictional behaviour of non-metals with adhesion experiments using indium as one of the surfaces (Moore & Tabor 1952). With grease-free diamond surfaces the coefficient of adhesion σ (i. e. the adhesive force divided by the normal load) is about unity and is similar to that observed on metals. The junctions break at a short distance from the diamond interface, indicating that the adhesive bond is stronger than the bulk strength of indium. This is consistent with the suggestion that the adhesive forces at the diamond surface may be responsible for the frictional properties of diamond.

In the attempt to discover a rational chemotherapeutic treatment tor cancer, the influence of various dyes on malignant growths has been investigated. There has resulted a considerable difference of opinion as to the effect ofintra-vitamstaining upon tumour growth. Since many acid dyes when injected into the living animal readily stain certain types of cells, the present investi­gation was carried out primarily to determine whether malignant cells stain intra-vitally with trypan blue, as do their normal prototypes. i.Previous Work.—The dyes which have been employed most in vital stain­ing are tam in blue and trypan blue. According to von Möllendorff (1921) isamin blue is precipitated at the site of injection, and produced a localised vital coloration; it slowly passes into solution again and results in time in a general staining of the animal. Trypan blue, on the other hand, is one of the most suitable of the acid dyes for effecting direct intra-vitam staining.

Growth and morphogenesis of the young fern gametophytes. e. g. Dryopteris filix-mas, is completely controlled by light. This remarkable light effect has nothing to do with photosynthesis but is a good example of photomorphogenesis, i. e. direct control of growth and development by light (MOHR und OHLENROTH)1. — Only short-wave-length visible light (“blue light”) has been found to the photomorphogenically effective. Under longer wave length visible light (“red light”) the sporelings continue to grow as “etiolated” filaments very similar to those formed in darkness, while under blue light “normal” two dimensional growth and prothallium formation can occur. The induction of morphogenesis by blue light is causally connected with an increase of protein synthesis. Sporelings growing in the blue contain much more protein (as related to dry weight) than sporelings growing in the red at about the same photosynthetic rate (OHLENROTH und MOHR)2. In the present paper it has been shown that the size of the chloroplasts in cells of these sporelings can be controlled by light. In darkness the chloroplasts are smaller than in red or blue but in blue they become much larger than in the red. This control of plastid size by light is reversible, e. g. if sporelings which have been grown in the red are kept under blue light the chloroplast size increases rapidly up to a certain value but if they are brought back into the red the original size will be regained within a few days. It has been concluded that the protein content of the plastids is controlled by light and that changes of the plastid size are manifestations of a change in protein content of the plastids.

Though many attempts have been made to produce a beam of polarised X-radiation and to detect the polarisation by such methods as are applicable to ordinary light, the experiments have proved unsuccessful, and no evidence of polarity has been obtained. An arrangement of molecules such as occurs in crystals does not appear to affect a beam of this radiation transmitted through the crystalline substance. The experiments here described were suggested by the results of an investigation of secondary radiation proceeding from gases and certain solids subject to X-rays, for it was found that the gases experimented upon were the source of a radiation differing little in character from the primary radiation which produced it. In some respects the difference was inappreciable, as, for instance, in the absorbability of the radiations by aluminium. The primary and secondary radiations differed slightly, however, in their ionizing powers in air. The energy of this secondary radiation was found to be proportional to the mass of gas through which the primary beam of definite intensity passed, and to be independent of the nature of the gas.

Children to whom fractions have been presented in a meaningful manner, know that certain fractions equal, or are the same size as, other fractions. This knowledge has been acquired by the actual division of objects, by using blackboard drawings or the flannel board, by studying fraction charts, and by counting fractional parts. Later, when pupils add simple fractions (like ¼ and ¼) mentally, someone will always give the answer as ¼ This provides the teacher, or another pupil, with the opportunity to state that “2/4 equals, or is the same as, ¼” Therefore, when the class is ready for reduction of fractions, a previous knowledge of equal fractions forms the basis for the new concept.

This paper reports the first Raman spectroscopic study of the potassium complex of the cation-specific antibiotic valinomycin. Complete Raman spectra (140 to 3600 cm−1) of crystalline valinomycin-KSCN and its CCl4, CHCl3 and C2H5OH solutions are presented and used to probe the structure of the complex in these environments. In all cases a single, narrow peak is observed in the ester CO stretch region (1750 to 1775 cm−1) which contrasts strongly with the broad bands observed in solutions of uncomplexed valinomycin. This is consistent with the presence of a single conformation in which all six ester CO groups co-ordinate an enclosed potassium ion. We find that although the ester CO stretch frequencies of the complex are similar in the solid state and in non-polar solution (~1770 cm−1) they are considerably different in the presence of polar solvents (~1756 cm−1); this may indicate that the complexed potassium ion is still free to interact with nearby solvent ions (and possibly its counterion) through gaps in the hydrophobic “shield” provided by the hydrocarbon residues of valinomycin. In contrast the amide CO frequencies of the complex (~1650 cm−1) are solvent-independent. These groups are apparently strongly hydrogen-bonded to provide a rather rigid, compact framework for the complex conformation.

Ionophoresis of Sugars on Paper and Some Applications to the Analysis of Protein Polysaccharide Complexes

There are very few reactions the rate of which can be measured both in the gaseous state and in solution. Several bimolecular reactions have been investigated in solution, and since the rate of a bimolecular gas reaction can be calculated from the equation Ink = In Z — E/RT, where E is heat of activation and Z the collision number, the rate of reaction in solution can be compared with that of the hypothetical corresponding gas reaction. The observed velocity constants in solution have usually been found to be smaller by several powers of 10 than the calculated values. On the other hand, as shown in the previous paper, in the one example where direct comparison has been possible, namely, the decomposition of chlorine monoxide, the rate in solution in carbon tetrachloride is the same as that in the gas phase. Thus it is evident that the retardation of reactions by certain solvents is a specific action and need not occur in an “ideal” solvent. The rates of unimolecular gas reactions cannot be calculated, and direct comparison has hitherto been possible only in two examples. The equation Ink = 31•69 — 24,710/RT has been found to represent the rate of decomposition of nitrogen pentoxide in the gaseous state and in a series of eight similar, chemically rather inert, solvents. In nitric acid or in propylene dichloride, however, In Z increases by several units and E becomes 28,300 calories. Daniels regards as “normal” those solvents which do not produce an alteration in E, and as “abnormal” those which cause a deviation from the value characteristic of the gaseous state. The solvents in which the decomposition of nitrogen pentoxide could be studied were naturally not very varied in character, since most liquids would be attacked chemically. Thus the impression which the results tend to convey, namely, that “normal” or "ideal" behaviour is more common with unimolecular reactions than with bimolecular reactions, may be an illusory one. In the only other known example, the isomerisation of pinene, the rate of reaction in the gas, in the liquid, and in carbon tetrachloride is the same.

Although the carbon precursor of glucosamine has been studied in many organisms (l-5), only recently has work been done on establishing the precursor of the nitrogen atom. A preliminary report from this laboratory (6) showed that ammonia was an excellent source of this nitrogen. Recent work by Leloir and Cardini (1) has shown that, in a crude enzyme system from Neurospora crassa, the amide group of L-glutamine was the precursor of the nitrogen of glucosamine. This same observation has been made in experiments with rat liver (7) and streptococci (8). Ammonia itself can also be the source of this nitrogen atom in the synthesis of glucosamine 6-phosphate by the glucosamine-6-phosphate deaminase system prepared from Escherichia coli (9) and from rat and pig liver (10). In this paper are presented the details of the previously reported findings, and data are presented showing that ammonia nitrogen is a precursor of the nitrogen atom of glucosamine isolated from the ovomucoid of the chicken egg.

A description is given of a simple method of determining the sensitivity of bacteria to sulphonamides by means of impregnated blotting-paper disks applied to nutrient agar prepared from broth freed from sulphonamide antagonists by incubation with lysed horse red blood cells.With organisms sensitive to the selected sulphonamide, a zone of inhibition of growth will occur, the diameter of which is related to the concentration of the sulphonamide necessary to inhibit growth. Sensitivity to several sulphonamides can be determined simultaneously.The impregnated disks can be stored without loss of potency.

Frog’s nerve-fibres present very different appearances in different portions of their length, when teased and examined in Ringer’s solution. The main distinctions affect the contents of the myelin sheath. To avoid misunderstanding I propose to speak of this portion of the nerve-fibre as the “intramyelin material,” since the term more generally used (“axis-cylinder”) has now become so completely identified with new appearances produced in this material by the action of reagents. Briefly summarised the main differences observed are as follows:― ( a ) In places the intramyelin material exhibits the perfect transparency and homogeneity of a clear solution.

THE use of metal phthalocyanines as catalysts for the oxidation of organic compounds has been described in the literature. A number of papers by C. Paquot have reported the catalytic activity of the nickel phthalo-cyanine in the oxidation of long-chain fatty acids and their esters1, saturated ketones2, benzene hydrocarbons such as toluene and ethylbenzene3, cyclohexane hydrocarbons4, and pinene5. In addition, M. Baldwin reported the oxidation of olefins, principally isobutylene, by copper phthalocyanine supported on pumice6. A. Cook7 described the activity of iron phthalocyanine for the catalytic decomposition of hydrogen peroxide. A slow degradation of the catalyst was observed which was ascribed to a complex formed between the peroxide and the phthalocyanine. On the basis of these reports, a number of phthalocyanines were tested as cathode catalysts in fuel cells.

Many investigations have been made of the salt exchange between slices of plant storage organs and solutions in which they have been placed. A simple form of experimentation is to place the pieces of tissue in water devoid of solutes, and to investigate the drift with time of the concentration of the external solution. The concentration of such a solution was used by Stiles and Kidd (1919) as a base line from which to calculate the absorption of salts by the tissue when placed in a salt solution. For example, the conductance of distilled water rose by 190 units in 52 hours when carrot tissue was placed in it, whereas that of 0·0002 N KCI increased only 137 units, whence it was deduced that the carrot tissue had absorbed KCI to the extent of 53 units of conductance. The justification for this procedure is doubtful, since a solution with which the tissue was in equilibrium would show no change of conductivity, and yet by this method of reasoning would be said to have lost salt to the extent of 190 units of conductance. More recently stiles (1927) has made detailed studies of the problem of the exosmosis of substances from slices of various storage tissues, including carrot root, into distilled water. Well-washed discs of tissue were placed in water and shaken continuously at 20° C. The drift of the conductance of the outside solution was followed. It rose for about 24 hours and then fell slowly for about 10 days, after which a steady value was maintained for some time until the conductance rose as the tissue died. The concentration of the outside solution was also determined by the weight of the residue after evaporating the solution to dryness. The concentration so determined followed the same course as the conductance. Stiles suggests that the initial liberation of electrolytes, which is greater the shorter the preliminary washing, takes place from the cut surface-cells and from the veils underneath, which soon die. These electrolytes are absorbed by the remaining living cells at a rate which is eventually greater than that at which they are liberated, with a consequent tail of the external conductivity. The tissue, small in bulk relative to the solution, would have to absorb the greater part of the electrolytes liberated. There is no direct evidence in favour of such an explanation. As far as we know, tissue, such as Stiles used, never decreases the conductivity of such dilute solutions, except in experiments of the type which we are trying to explain.

The carbohydrate of ovomucoid was analyzed for components I, II, III and IV which were, fractionated by CMC-column chromatography. The total hexose content and the molar ratio of d-mannose to d-galactose (4:1) were identical in each component, but the d-glucosamine and sialic acid contents were found to be higher in components I and II (both are trypsin inhibitors) compared with components III and IV (both are apo-proteins of flavomucoid). The amino acid composition of each component of ovomucoid varied considerably. There were remarkable differences in the amino acid composition between components I and II, both had an antitryptic activity. The N-terminal amino acid of components I and II was alanine and in the case of components III and IV, threonine was found on the N-terminal. The free carboxylic residue of sialic acid was found to be responsible for the negative charge of ovomucoid, and its electrophoretic heterogeneity was reaffirmed by paper electrophoresis. It is evident from the ultracentrifugal ...

1. The whey proteins of guinea-pig milk were examined by electrophoresis on paper, cellulose acetate, starch gel and polyacrylamide gel. 2. Two major proteins were detected, one of which was identified as blood serum albumin. 3. The major whey protein was isolated by CM-cellulose chromatography and on columns of Sephadex G-100. 4. The amino acid composition of the protein, taken in conjunction with its other properties, indicated that the major whey protein in guinea-pig milk is homologous with cow alpha-lactalbumin and that beta-lactoglobulin is absent from guinea-pig milk. 5. Guinea-pig alpha-lactalbumin, which was obtained crystalline, had mol.wt. 15800, N-terminal lysine and C-terminal glutamine.

It has been shown in a previous paper, that during a radioactive transformation involving the expulsion of an a particle, the residue of the atom from which the a particle has been expelled recoils in an opposite direction to that in which the a particle is emitted, and can travel a considerable distance through a gas if the pressure is sufficiently low. A similar effect was also demonstrable in the case of the transformation of radium B into radium C, although this transformation is supposed to be accompanied by only β rays. The phenomena associated with this recoil are studied in this paper. In the first place it was found that it was only in certain circumstances that pure radium C free from radium B was projected from a plate coated with radium B and radium C. The reasons for this were two-fold: firstly, only a very small fraction of the radium C produced from radium B escaped from the plate so that even a small quantity of radium A on the plate was capable of emitting a comparatively large quantity of radium B. Secondly, the active deposit on a plate appears to be concentrated into heaps, so that radium C in breaking up mechanically carried with it some radium B. If, however, sufficient time is allowed after removing a plate from the emanation for radium A to completely decay and if, further, sufficiently small quantities of deposit are used to avoid the formation of heaps, practically pure radium C is emitted. The law according to which the radiation fell off with distance was also studied, and it was found that radium C is not emitted from an active plate equally in all directions, a greater quantity being emitted normally to the plate than in directions making an angle with the normal. The absorption by air of radium C when it recoils from radium B was investigated. Although the experiments were difficult to perform owing to the ease with which the radium C is stopped by the air and owing to uncertain changes in the radiating power of the plate, it was possible to get some estimate of the penetration of radium C. It was found that about half the radium C projected from a plate was stopped by 2.5 cms. of air at a pressure of 0.04 mm. mercury. Since radium B emits only β particles, the energy of recoil in this case should be less than one-millionth of the energy of recoil in a transformation in which an a particle is emitted. The fact that the penetration of radium C when it recoils is as much as one-fortieth of that previously found for radium A and radium B is therefore surprising. All attempts to stop radium C by an electric field when it recoils have failed, indicating that radium C when formed from radium B either remains electrically neutral or, as is suggested by the absorption experiments described, the energy of a recoiling atom of radium C is for some unknown reason greater than has been supposed.

The original methods for measuring d -amino acid oxidase in animal tissues involved the use of either phosphate buffer (Krebs, 1935), phosphate buffer with added arsenite (Rodney and Garner, 1938), both at about pH 7.5, or pyrophosphate buffer at pH 8.6 (Krebs, 1939). The two papers found which contain values for this enzyme in chicken tissue (Trufanov and Pavlova, 1951; Williams et at., 1949) described methods employing phosphate buffer. A study of the effect of buffer and pH on the assay of purified pig kidney d -amino acid oxidase by Walaas and Walaas (1949) revealed that pyrophosphate buffer at pH 8.3 gave optimum results. Pyrophosphate buffer appears to have been used more frequently than phosphate buffer in mammalian studies (Burton, 1955). This note presents the results of comparisons of these and other buffer systems used in the measurement of this enzyme in chicken tissue. The buffer systems were compared in the following …

The method of analysing a beam of beta-particles by deflecting them with a magnetic field in a vacuum has long been known. The beta-rays of Radium B + C, examined by this magnetic focussing method give a ‘’continuous spectrum” of beta-particles over a wide range of velocities, on which are superposed lines which are ascribed to the conversion of gamma-rays into beta-rays in escaping from the radioactive atom. There has been considerable difference of opinion as to the origin of the continuous spectrum, whether it consists of the electrons ejected from the nucleus in its disintegration, or whether it is merely secondary in origin. For example, Pohlmeyer, after some experimental work, recently came to the conclusion that the continuous spectrum of Thorium B + C might be due merely to lack of resolution of the line spectrum. He argued that this was probably true also of the spectrum of Radium B + C, a view previously maintained by Meither. The relative velocity-distribution of the particles from Radium B + C was examined by Chadwick,! using an electrical counter, and by Chadwick and Ellis, using an ionisation-chamber. In the latter case it is necessary to know the law of the variation of ionising power with velocity of the particles, as well as to estimate the reflection from the walls of the ionisation-chamber it is difficult to determine these quantities with accuracy. In the measurements by W. Wilson the beta-particles were deflected by a magnetic field into a Faraday cylinder, and the rate of accumulation of charge was directly determined. In the course of experiments made in this laboratory last year, Mr. Curtiss showed that this method could be combined with good focussing if a sufficiently sensitive electrometer were used ; an account of the work has been given.

This paper is conveniently divided into three parts. In part (i) an account is given of the effect of finely divided particles on the rate of evolution of gases resulting from chemical changes ; in part (ii) the phenomenon of initial acceleration, as also the effect of variation of pressure on the evolution of gases, is discussed; in part (iii) the case of the decomposition of formic acid into carbonic oxide and water is investigated under constant conditions, other than those of the mass of reacting substances and of temperature.

For the purpose of researching differences in nucleotides between healthy and dwarf diseased rice plants, ribonucleic acid (RNA) was prepared from rice plant leaves by a modified Kirby's method. Nucleotides were then obtained from the RNA by mild alkaline hydrolysis, and their quantitative conversions were observed.(1) For preparing RNA from rice plant leaves, the procedure described in the authors' preceeding paper was again modified. According to this schedule, the rice-RNA could be obtained more rapidly and more easily, with higher purity and homogenity, both from chemical and physicochemical points of view.(2) Purine-to-pyrimidine ratio (Pu/Py) of the RNA from dwarf rice plants was from 0.88 to 1.34, the ratio of adenylic acid plus uridylic acid to guanylic acid plus cytidylic acid (A+U/G+C) of the same RNA was from 0.68 to 1.00. The values of Pu/Py and A+U/G+C of the RNA from healthy rice plants were from 0.73 to 1.28, and from 0.60 to 1.02, respectively. Nucleotide compositions of the RNA, therefore, appeared to be rather similar between healthy and diseased rice plants. It is, however, noticeable that the ratio of guanylic acid to adenylic acid is larger, and guanylic acid content of RNA is larger in the diseased plants than in the healthy plants.

The object of the present investigation was to obtain some further evidence on the apparent production of neon and helium by electric discharges in vacuum tubes, which has been described by Collie and Patterson. Strutt has recently attempted to repeat these experiments, using methods somewhat different to those of Collie and Patterson, with negative results.

The elasticity of polymer melts is of major concern in the processing of plastics. It is usually reflected by dimensional changes. Since the swelling of polymer extrudates depends on the capillary dimensions and the volumetric flow rate, the blow-up must be examined over a range of conditions. Of course, the swelling is also dependent on polymer structure. Consequently, variations in materials and operating conditions necessiate changes in tooling. This paper describes the swelling behavior of several different polymer types and illustrates that viscosity measurements can not be used to predict elasticity.

A small amount of arsenic has been determined colorimetrically by using silver diethyldithiocarbamate in pyridine (Ag-DDTC method). On the other hand, H. Bode reported that a similar reaction also occured in Ag-DDTC chloroform solution by an addition of several solid organic bases such as ephedrine. Recently, S. Nakao et al. obtained a good result by an addition of dimethylformamide.In this paper, 24 kinds of liquid organic bases were examined. This method based on the fact that AsH3 reacts with Ag-DDTC in chloroform containing the bases, and the light absorption and the calibration curve of colored products were examined.The amount of Ag-DDTC and of organic bases in the samples were 1.03×10-4 mole and 3×10-2 mole in 10ml of chloroform solution, respectively. However, in the case of triethylamine, 0.26×10-4 mole of Ag-DDTC in 10ml of chloroform was enough for this purpose. It was concluded from the results that the bases which give an absorption in the visible region to the solution are triethylamine, 2, 4-lutidine, 2, 6-lutidine, α-picoline, β-picoline and γ-picoline. The calibration curves obeyed Beer's law in the concentration range from 1 to 25ppm.Among these bases, triethylamine gave the best results, namely, in the case of triethylamine, the amount of Ag-DDTC necessary was quarter of other cases. Therefore the authors concluded that triethylamine, which has less offensive smell and is cheaper than pyridine, can be used for the determination of arsenic with Ag-DDTC instead of pyridine.

The ras − mutant of Escherichia coli K-12 is sensitive to ultraviolet (UV) light but only slightly sensitive to X-irradiation (1.5-fold increase). Other phenotypic properties include normal recombination ability and normal host cell reactivation ability but an abnormally high frequency of UV-induced mutation. The response of the ras − mutant to UV has been studied biochemically. After low doses of UV, the ras − mutant degraded excessive amounts of deoxyribonucleic acid, and long delays in resumption of deoxyribonucleic acid synthesis occurred. Pyrimidine dimers were excised at the normal rate. Although the mutant had the capability of initiating repair replication, the process was not completed after the high UV dose required to allow detection of repair replication. The ras − mutant, after low UV doses, left three to four times as many single-strand breaks not rejoined as did the wild-type strain.

Urinary cetylpyridinium chloride (CPC)-precipitates and non-CPC-precipitates in normal male children and seven patients with a new type of mucolipidosis, GM1-gangliosidosis type 1, I-cell disease, Hurler syndrome, Morquio syndrome, Gaucher's disease adult type and Tay-Sachs disease were studied using several methods including Sephadex G-25 gel filtration, ECTEOLA-cellulose column chromatography and enzymatic digestion with chondroitinase ABC. 1) Considerable amounts of glycopeptide fractions were detected in the urine of the patients with a new type of mucolipidosis, Gm, -gangliosidosis type 1, I-cell disease and also Gaucher's disease adult type compared with that of normal male children and other patients. 2) The total acid mucopolysaccharides excreted into the urine from two patients with Hurler syndrome and Morquio syndrome were much higher than those excreted in normal male children and other patients. 3) Large amounts of the chondroitinase ABC-resistant acid mucopolysaccharides were found in the urine of patients with Hurler syndrome, Morquio syndrome and GM1-gangliosidosis type 1.

INTRODUCTION I would like to discuss some results concerning the improvement of the physical properties of HWM-fibres, and in particular, present some remarkable properties of a new fibre recently obtained in our research laboratory. In the past few years there has been a great deal of interest in the manmade HWM-fibres. These fibres may be divided into two groups according to their physical properties, namely Polynosic fibres produced by the Toramomen process and others which do not quite reach the standard of Polynosic fibres. For the sake of brevity I shall call them simply HWM-fibres. These HWM-fibres have essentially an initial wet modulus ranging between 10 and 20 g/den. while the modulus of Polynosic fibres is 20 to 60 g/den. Basic references for these properties are the recent papers by Professor Mark' and by Dr. Treiber2.

AN approximate identification of sugars separated from hydrolysates of biological material can usually be made by paper chromatography. Positive identification is usually achieved by the measurement of some specific physical property such as optical rotation, or the preparation of derivatives possessing characteristic melting points. It frequently happens that sugars separated from hydrolysates are present in insufficient amounts to enable such methods of identification to be used.

The characteristic property which some molecules have of trans­mitting influences from one part to another is an indication that the electrons constituting the bonds cannot be segregated into closed localized pairs. This feature is represented in the Pauling method by the super­ position of a number of canonical structures, each of which corresponds to a chemical picture of localized bonds. The state of the molecule has properties which are different from those of the individual canonical structures, but can be defined or interpreted in terms of a set of them. The energy of the lowest or normal state is usually lower than that of any one canonical structure, even than that which would appear from the orthodox method of drawing bonds to be the most stable. The amount by which the energy sinks as a result of the superposition has been called resonance energy by Pauling, and numerical estimates of its value have been made for a large number of organic molecules. In calculating this energy change, however, no account seems to have been taken of the change in the lengths of the links which may be caused by the interaction of the electrons. Links are regarded as single or double, and the appropriate energy content calculated as though they were isolated single or double links, whereas the interaction between adjoining links may result in a length and an energy of link, to which the description single or double is no longer appropriate. Pauling has recently discussed the relationship between the nature and the lengths of links in typical organic molecules. Taking the known lengths of links in ethylene, benzene, graphite, and ethane, and the frac­tional order of their links (as two, three-halves, four-thirds, and unity) derived from the coefficients which occur in the linear sum of canonical structures, Pauling has derived an empirical relation between them. From it he deduces in other cases the extent to which the double-bonded character enters into other links. Pauling’s method will be made more precise in a paper which follows this.

Loch Craiglin cannot be considered as merely an isolated basin of Loch Sween. Its shallowness, the great growth of vegetation round the shore and the fluctuations in salinity make it atypical. On the more complete isolation of the loch with the making of the dam, these conditions led to a lack of circulation, a consequent development of hydrogen sulphide in the deep water and very high pH values near the surface. One could not therefore expect the plankton to be very similar to that in the outside loch (see, however, Marshall, 1947). Unfortunately there are no records of seasonal variation before fertilization was begun. In spite of these drawbacks Loch Craiglin was a convenient and manageable area for small-scale experiments on fertilization.The experiments may be divided into two groups, those which were not followed up in detail and those in which the plankton and hydrographic results were followed from day to day. The former, made during the earlier stages of the work, are mainly described in the previous papers and led to the conclusion that the richness in phytoplankton of Loch Craiglin in 1943 was probably caused to a large extent by fertilization. Those of the second group, described above, were made to test special points and different fertilizers. Two experiments made during the summer of 1944 had apparently no effect on the phytoplankton but a third in which a very large excess of fertilizer (ten times the normal quantity) was added, gave a good increase after an initial lag. At that time the attached algae were abundant and their needs apparently had to be satisfied before any nutrients could be used by the phytoplankton.The remaining experiments, which were therefore made during the winter, showed that commercial ammonium sulphate, ammonium nitrate and monoammonium phosphate could replace the sodium nitrate and superphosphate used hitherto. Two further experiments in the following spring using ammonium chloride and urea did not, however, prove effective. All the salts used had been found in laboratory tests by Miss F. A. Stanbury to be suitable for diatom growth, and the reason for the failure of these two in the loch is unknown.The utilization of the nutrients was extremely rapid even in winter but it is probable that their disappearance is not entirely caused by the phytoplankton or bottom-living algae but partly by adsorption on the bottom mud or by suspended matter. On one occasion it may have been caused by a serious fall in loch level.The zooplankton which during the first year of fertilizations was richer in Loch Craiglin than in the outside loch diminished in the second year and remained poor thereafter in spite of, or perhaps because of, the intensive fertilizations. The dense phytoplankton and other vegetation raised the pH at times to levels dangerous to animal life.

In this paper, flux compositions used for brass welding by oxy-acetylene flame were as follows;(1) Fused borax-boric acid system(2) Mixed borax-boric acid system(3) Fused borax-boric acid-sodium chloride system(4) Fused borax-boric acid-disodiurn phosphate system(5) Fused borax-boric acid-NaH. NH4PO4 systemThese fluxes were applied as a paste to the welding rod, but did not painted on the surface of the parent metal.From bead apperance, slag fluidity, porosity and mechanical properties on Vee butt joint, borax 20%, boric acid (80%) flux is excellent.Addition sodium chloride, disodium phosphate, NaH. NH4PO4 to borax-boric acid flux is not advantageous.

This paper is an extension of a previous memoir on the “Colours in Metal Glasses and in Metallic Films”; it is concerned with the application of mathematical analysis, akin to that already there developed, to the explanation and coordination of the colours which certain metals are, under a great variety of circumstances, capable of causing. From observations on gold and copper ruby glasses, it has been shown that the first stage in the formation of a crystal of those metals is the small sphere; and from observations on the growth of sulphur crystals in CS 2 , Vogelsang arrived at the conclusion that the small sphere is always the first stage in the formation of a crystal. He remarked, however, that it is by no means necessary that each of the small spheres, formed as crystallisation commences, should give rise to a separate crystal: the small spheres tend to coagulate, forming first rows and then groups of other and more complicated shapes, until the crystal is ultimately formed. To the intermediate bodies he gives the name of crystallites .

Although copper salts are such effective poisons for the lower forms of life, little work has been done with any of the copper compounds as anthelmintics, except for the extensive investigations of copper sulphate in trichostrongylid infections in sheep and some recent reports on the efficacy of certain proprietary copper anthelmintics. Because of this the action in vitro of a number of common cupric salts was tested against Strongylus vulgaris. The present paper reports the toxicity of cupric sulphate, chloride, fluoride and bromide for this parasite.

A dose of Beta rays can be given to Jensen’s rat sarcoma (J. R. S.) which is just enough to prevent the cells growing when transplanted into normal susceptible rats ; this has been referred to as the lethal dose (1). It is not known whether this effect is produced by inhibiting mitosis or whether growth is interfered with so that cells fail to mature, thus cutting off the supply of potentially dividing cells. The following experiments were designed to show especially how the growth and division of sarcoma cells are affected by exposure to measured doses of Beta radiation. Independent experiments by Hertwig (2) and by one of us (3) have shown that cells are most susceptible to radiation when they are in a state of division. On the other hand, it was shown by Wedd (4) that cells of a mouse carcinoma which had received a “ lethal dose ” of Beta rays could still be found in a state of mitosis as long as six days after they had been inoculated into a susceptible animal. It will be seen, however, from the context, that it is possible to reconcile the idea of the state of mitosis being one which is peculiarly vulnerable to radiation with the fact that, after a lethal dose, numbers of the cells are afterwards found in mitotic activity.