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An apparatus is described which permits of efficient and simultaneous extraction of a large number of paper strips, as in use in paper electrophoresis. The fully automatic procedure reduces the amount of work required to a minimum.

The design and manipulation of an apparatus for centrifugal acceleration of paper chromatography has been described. The main novel features consists of using filter paper strips instead of circular sheets and a constant flow solvent reservoir enclosed in the chromatography tank. Our arrangement is particularly suited for the quantitative analysis of materials labelled with radioactive isotopes of short half-lives and examples are given of the separation of some 82 Br- and 131 I-labelled substances. Advantages of the above method over circular paper chromatography are discussed.

ConclusionUsing a combination of two technics, paper chromatography in the first dimension and paper microelectrophoresis in the second dimension, it is shown that protein separation may take place during capillary ascent of a mixture of proteins on filter paper and that protein interaction may also occur.

Consden, Gordon and Martin reported a very ingenious method for the separation of amino acids by filter paper chromatography in which phenol or some other appropriate organic solvent sweeps the applied amino acids along the filter paper, capillarity causing the organic solvent to move. The percentage of light intermission along the chromatogram is measured and this transmission has been plotted on semi-log graph paper against the distance along the filter paper strips, and the areas of the segments above the plotted curve measured with a planimeter. It has been found that the areas so determined are over a limited concentration range a simple function of the concentration of the amino acids. The various factors which influence the reliability of this method are reported.

Paper chromatography is an analytical method for the separation of the components of mixtures of substances. A droplet of such a mixture in solution is placed on a small area of a piece of prepared filter paper, and a solvent is allowed to seep slowly through the paper. The compounds are washed along the paper at differing rates and, ideally, the mixture is separated into a series of spots along the paper, each spot consisting of a single component of the mixture. The sort of mixture which can be separated by this technique ranges from writing inks to complex mixtures of drugs extracted from biological materials. This paper describes an improved paper chromatographic technique for separating for identification the intermediate- and short-acting barbiturate hypnotic drugs—butobarbitone ( soneryl), amylobarbitone ( amytal), pentobarbitone ( nembutal) and quinal-barbitone ( Seconal). It is pointed out that 76 per cent. of cases of barbiturate poisoning studied in the Department of Forensic Medicine of the London Hospital Medical College in 1960 involved intermediate- or short-acting barbiturates and that in 20 per cent. of the cases two or more of these occurred together. The necessity of being able to separate and identify these barbiturates is of considerable importance both for medico-legal and statistical reasons.

Tritium labelled compounds on paper chromatograms are detected, localized, and the ratios of their activities determined precisely with a windowless scanner. Filter paper strip is pulled, by a wheel driven by a synchronous motor, between two windowless, flow, Geiger-Muller counters. The flow of argon saturated with propanol vapor provides an air-lock. Pulses from the Geiger tubes are fed to a precision, linear ratemeter and recorder with chart speed equal to that of the filter paper strip. The efficiency of counting tritium is low. The sensitivity limit lies aroung 3 m mu c/cm/sup 2/ of Whatman No. 1 filter paper. (auth)

The problems confronting the chemist in control of water treatment for an industrial boiler plant are very complex and dictated to a great extent by the pattern of plant operation. An interesting field of study is presented, particularly where the plant is modern in design and very extensive in the service it provides. The author has concerned himself principally with the problems of water supply and treatment at Aylesford Mills, as these are very typical of those which occur in other large industrial undertakings. Details are given of the feed water treatment plant for the medium- and high-pressure boilers, consisting of primary sedimentation units using lime, ferrous sulphate, and alum as chemical additives, followed by a filtration stage. This section of the plant is followed by a dual system comprising three base-exchange softener units and a fully automatic demineralization plant. The interesting features of fully automatic regeneration of the demineralization plant are discussed, together with the author's experience in operating this plant. Emphasis is placed on high standards of feed water treatment and the principles of the system adopted. Sodium sulphite and tannin are added as chemical deoxidants on medium-pressure plant. Hydrazine, together with a neutralizing amine, are used on the high-pressure boiler installation. The author concludes the paper with comments on the subject of boiler corrosion.

Cernik, A. A., and Sayers, M. H. P. (1971). Brit. J. industr. Med., 28, 392-398. Determination of lead in capillary blood using a paper punched disc atomic absorption technique. Application to the supervision of lead workers. The presence of lead in blood is the most incontrovertible evidence of absorption but hitherto the need for venepuncture has limited its determination in the supervision of industrial workers. Micro-methods using atomic absorption spectrophotometry (AAS) have, however, made possible the development of a sufficiently reliable test using a drop of blood obtainable by ear prick for use in the field for screening purposes. A micro-sampling method by AAS is compared with a routine polarographic procedure (POL) using venous blood (corr. coeff. = 0·990). The pipetting of microlitres of blood can be eliminated by spotting the blood onto filter paper, allowing it to dry in air, and then using a punched-out standard disc of dried blood for analysis instead. Correlation of this method (PD) with the micro-sampling technique (AAS) is good (r=0·981). The PD method using capillary blood also correlates acceptably with the micromethod using venous blood (r = 0·913). A pilot field study using capillary blood estimated by the PD technique showed that with this method blood can be collected by ear prick in factories for monitoring workers in the lead industry, thus eliminating the need for routine venepuncture.

A study with filter paper strips partially impregnated with the precipitating agent with or without colloid as the fixing agent reveals that in the case of spotted strips run in aqueous alcoholic mixture as the solvent, uniform bands of the precipitate are formed. In these cases, chromatographic observations such as measurement of ‘S’ and ‘Rf’ values is possible. Rhythmic structures can also be obtained with these strips when the reactant solution is used as the solvent. In the absence of colloids rhythmic structures are obtained at a high concentration and the bands obtained have to be washed and repeatedly dipped in hot water in order to clear the structure of rings present underneath. In the presence of colloid, rhythmic vertical bands are obtained at a much lower concentration and the clear interspaces are visible even without washing. Thus an independent method for obtaining rhythmic structures on filter paper with a technique very similar to chromatography has been developed.

A rapid polymerization method for in situ synthesis of polyethylene in a typical paper matrix of cellulose fibers is described. The unique properties of this double matrix, polyethylene in cellulose, are the result of performing the polymerization in a nonsolvent such that simultaneous polymerization and crystallization takes place yielding a nascent morphology. The morphology has been studied by scanning electron microscopy and was found to be different from what is usually obtained for melt crystallized polyolefins. Optical microscopy shows the polyethylene to be present as a complementary matrix with respect to the basic fiber construct. Mechanical, optical, and other properties of encapsulated filter paper have been measured using standard TAPPI tests. The results show a general improvement in physical properties for a range of “add ons” from 0 to 27%. Wet-strength and opacity undergo major changes.

Several qnantitative experiments were carried out on the filtration of fine particles of polystylene in dilute suspension using various glass-fiber paper filters. Each experimental run was performed at constant filtration rate by forcing the suspension through the filter using a syringe-type micro-injection pump. From the experiments, the following results were obtained within the range of experimental conditions.1) The so called log-penetration law is applicable to the thickness of paper filters. The basic equation for filtration could be expressed as eq. (3).2) The collection efficiency of a single fiber with the interference effect is given by eq. (13). The effect of direct interception seems to be the predominant mechanism for the collection of fine particles in dilute suspension in pure water by the glass fibers.Further studies are necessary on the effect of both the fibrous solid fraction in a paper filter and electrostatic forces on the collection efficiency in order to elucidate the proportionality constant in eq. (13).

Up to 20 mg of copper can be quantitatively separated from small quantities of gold, platinum and palladium, by ionophoresis on strips of paper pulp, 6 mm thick, 25 mm wide and 250 mm long. One millilitre of the hydrochloric acid solution of the metallic salts is placed on the paper, the ends of which are placed in cells containing 50 ml N HC1 and 25 ml N KC1. The paper is then moistened with N HC1. Carbon electrodes are used and are connected to a 12 volt D.C. supply, a current of about 200 milliamperes being recorded. The copper travels towards the cathode and after about 18 hours separates completely from the noble metals as a blue band about 75 mm in length. This band is cut out and used for the determination of the copper by electrodeposition, after decomposition of the organic matter by means of concentrated nitric and sulphuric acids.

A machine is described for the reproducible treatment of paper chromatograms with liquid chemical reagents. Strips of filter paper 5 cm wide are passed through the machine by two pairs of belts which grip the edges of the strip leaving the central area exposed on both sides. A film of liquid reagent is fed on to the undersurface of the paper strip by means of a roller and trough which is fed from a simple constant level device. The reagent-soaked strips pass immediately into a straight tunnel into which a stream of hot air is introduced by ports opening from manifolds running along the sides of the tunnel. The air stream is passed out of the top of the tunnel by means of an exhaust tube and fan connected to its distal end. The strips are passed out of the machine by disengagement of the belts which are returned to the starting point of the machine after being washed, and dried on their return passage through the hot air tunnel. Operating temperatures up to 150° can be achieved and are adequate for producing quantitative and complete reactions with the majority of color reagents that are useful for the quantitative estimation of substances by direct scanning of paper chromatograms (e.g. Zimmerman reagent, ninhydrin, phosphomolybdic acid). The mechanization of the treatment of paper chromatograms with color reagents improves greatly the reproducibility of the results, the evenness and reproducibility of background, and enables the successful use of color reactions which cannot be controlled sufficiently by manual methods to allow their quantitative estimation. It also enables the treatment of very large numbers of chromatograms: the present apparatus is capable of treating 40 cm long chromatograms at a rate of up to 88 per h or over 500 per day. The development, important features of design, and method of operation of the machine are described.

The collection efficiency of nine types of filter papers for air sampling was determined for monodispersed polystyrene latex aerosols by using a forward light scattering photometer. The aerosols were 0.091, 0.198, 0.365, 0.500 and 1.099 mu m in dia., which flowed through a test filter paper at a face velocity from 4.2 to 200 cm/sec. Toyo No. 660, No. 60 and No. LP filter papers exhibited minimum efficiencies at the face velocity range between 10 and 80 cm/ sec, and in the particle size range between 0.1 and 0.5 mu m. The collection efficiencies of Toyo No. 5A and Whatman No. 41 filter papers were over 95% for all the particle sizes at a face velocity higher than 100 cm/sec. Toyo HE-40, HV- 70, Toyo GB-100 and Gelman E filter papers showed collection efficiencies higher than 99%. The theoretical filter efficiency based on single fiber filtering mechanisms and the effect of neighboring fiber interference on the collection efficiency are also discussed. (auth)

The frequency of occurrence of defects in electrical insulation can be shown to follow the Poisson law of probability. One of the more important defects in thin paper insulation is conducting particles. In this paper expressions are derived for the probable breakdown voltage as a function of conducting particle occurrence. It is shown by statistical evidence that large conducting particles exist in the insulating paper and bridge one or more layers of paper in the finished capacitor through chance reorientation caused by manufacturing processes and operation. The degree and frequency of reorientation of particles with a typical grade of paper is determined experimentally, and the probable insulation thickness and consequent voltage strength of various size capacitors is calculated. A method of determining the optimum voltage strength of this insulation is illustrated. It is concluded that conducting particles are a predominant factor in determining the voltage strength of present day capacitors and that one of the greatest opportunities for improvement lies in the reduction of the conducting particle content in the paper.

This paper describes the characteristics and properties of a new insulation system currently used to manufacture high-voltage bushings at voltage ratings of 15 through 69 kV for transformers and switchgear apparatus. The system is compared with other forms of insulation such as phenolic-paper, oil-paper, mineral-filled epoxy, and electrical porcelain. Its application in high-voltage condenser bushings is also discussed. With this new insulation, epoxy resin is used to totally impregnate an electrical grade of kraft paper resulting in a resin-rich (approximately 70 percent) material having unusual properties. Its predominant characteristic is the complete absence of voids resulting in high-corona-inception voltages and high-dielectric strength. It also has excellent physical properties which, coupled with a flexible manufacturing process. open up numerous new design possibilities in high-voltage engineering.

FARADAY's paper "On Argument" was read in August 1818 to a semiphilosophical, semi-social group of young members of the Royal Institution to which he belonged. It was entered by his hand into a kind of record book containing the proceedings of the group. This book was in the private possession of one of the members of the group who left London, and was later, in 1890, presented to the Royal Institution, according to his will. This explains why "On Argument" was not even mentioned in H. Bence-Jones's Life of Faraday of 1870. It is not for me to explain how such an interesting paper escaped publication before now. I am most grateful to the Royal Institution for the permission to publish it, and especially to their Librarian, Mr. K. D. C. Vernon, who drew my attention to it. In this paper Faraday speaks of attributing foolish or improper opinions to, and of making unwarrantable assertions about one's opponent; and he stresses that he has in mind definite experiences of his own. It may therefore be relevant to mention an example, and I therefore decided also to publish, by way of preamble to the paper, a remarkable though yet unpublished letter from G. Moll to Faraday dated 25 April 1831. This letter is in the possession of the Institute of Electrical Engineers, to which I am indebted for permission to publish it. G. Moll of Utrecht was a personal friend of Davy and of Faraday. He was famous as a chemist and as the (anonymous) author of the remarkable On the Alleged Decline of Science in England (which is a comment on C. Babbage's famous The Decline of Science in England and was edited and published by Faraday in 1831). Moll's letter accompanied the manuscript of that book. It contains a comment on Dr. J. A. Paris' Life of Davy, and a description of an attempt of a group of French philosophers to suppress Davy's criticism of Lavoisier. Moll protested against the lack of any reference to this incident in Paris' book. It is interesting to note that the silence still prevails. Only John Davy, in his Life of his brother, referred to this incident, though rather evasively; he discussed it in a little more detail in his Fragmentary Remains of Sir Humphrey Davy. But none of the later biographers of Davy or Faraday refer to this incident and Moll's letter was ignored until now. For my own part I see no reason for concealing the failings of the great men of the

Two major improvements on a high voltage paper electrophoresis apparatus are described. Special tinned brass radiator plates have been very effective for cooling the system. Multichambered electrolyte vessels have facilitated the separation of various biological mixtures at several pH's in a single run at room temperature.

IPC-1478 filter paper efficiency was evaluated using polystyrene latex and dioctyl phthalate (DOP aerosols). Efficiency was measured as a function of particle size, filtration velocity, and filter mass loading. Experimental results of 0.557-µm and larger particle sizes indicate that this medium has limited effectiveness under high-velocity and high-loading conditions. Differences in efficiency were observed when this medium was tested with solid and liquid aerosols.

In dc cables the resistivity of the insulation is a very important parameter, as it determines the stress distribution and the power losses in the insulation. This paper gives the results of several tests on plane capacitors, from which the steady-state resistivity of four different kinds of paper and impregnants appear to be almost identical from this point of view. The transient behavior of one of the dielectrics is also shown, giving the current density as a function of time after the application of a direct voltage, for different temperatures and stresses.

A method is described for the fractionation fo DNA preparations on DEAE- cellulose paper. This paper can be used as strips or as centrifuged paper pulp. In both cases, similar results are obtaiend. The reproducbility and the senstivity of the fractionation are very high. During the fractionation process, the desorption of the macromolecular species is complete. Some of the fractions obtained can be rechromatographed and eluted in the same position. The additivity of the fractions evidences their preexistence in the preparation. The use of cellophane strips enables the complate fractionation to be run in ten hours; with centrifuged paper pulp, a complete elution requires two hours. The physicochemical properties of the DEAE-cellulose paper allow a desorption of the highest molecular weight DNA molecules at neutral pH. These results are discussed and several examples of fractionation of polynucleotides derived from DNA are given.

The results obtained here consistently failed to show deviations from Beer's law for optical densities less than 1.4, and the use of scanning as a convenient method for differential protein estimations would appear to be justified. The methods described may enable other workers to make similar tests of the method with a minimum of preliminary development, and some may succeed in obtaining significant failure of Beer's law in their apparatus. The use of apparatus of this type would enable the variation of the deviations with arrangement of the optical system, etc., to be worked out, but the following experimental conditions are already known to lead to significant deviations: 1. Use of dry paper instead of lightly oiled paper. 2. An inadequate light ifiter for the photocell. 3. An illuminated slit too long to be completely covered by the protein pattern. 4. Variations in protein density over the slit, either because the slit is too wide or because the protein pattern has been applied unevenly. 5. Use of low quality ifiter paper containing "pin holes." 6. A dye uptake which is not proportional to protein content of the paper [Martin and Franglen (14)]. The failure of Crook, Harris, and Warren (4) to substantiate Beer's law does not indicate the most general situation for the application of the scanning method. The application of Beer's logarithmic law to the scanning of dyed protein patterns has been investigated by methods described in detail. No deviations could be found for optical densities less than 1.4 for amidoschwarz 1OB or less than 1.1 for azocarmine B staining. The scanning method can be used for evaluation of protein fractions if care is taken.

THE HISTORY of the paper industry and the history of paper machine drives is a story of continued progress; progress in improved performance, increased reliability, and operator convenience.

The objective of the work reported in this paper was to study the influence of the thickness of the paper mass and of the inner temperature distribution on the vacuum drying process; particularly to study the ways in which these two factors affect the quantitative distribution of residual moisture perpendicular to the layers of the paper. The quantitative distributions of residual moisture perpendicular to the layers in soft paper masses 0.3 to 2.4 cm thick were determined. The results show that both the magnitude and distribution of temperature throughout the paper affect the degree of drying. Neither a low vacuum nor a prolonged drying time will compensate for an unfavorable temperature distribution. The magnitude and distribution of temperature predominate over the effect of paper thickness. With unfavorable temperature conditions, paper only 0.6 cm thick will retain an excessive amount of moisture. With favorable temperature conditions, paper 2.4 cm thick can be dried under vacuum to an acceptable moisture content. The upper limit of residual moisture content for transformer insulating paper that can reasonably be expected to be achieved is about 0.5 percent, not 0.1 percent or less.

A device for scanning electrophoresis and chromatography paper strips is described. A pen recorder traces the curves of the optical density, integral of the optical density, radioactivity intensity and integral of the radioactivity intensity as a function of position of the paper strip. The scanning is carried out automatically.

Filter paper has been tested as a medium for the collection of blood samples for the subsequent elution and analysis of phenylalanine, tyrosine, glucose, and urea nitrogen. The use of paper did not measurably alter the precision of the above methods. The paper punch as a means of quantification has been compared with the more commonly used technic of volumetric measurement. The precision obtained with punched spots was found to be similar to that found with measured spots for the above four procedures and for weighed samples. The hematocrit value was found to have an influence on the volume of blood contained in a punched spot. Differences in spreading through filter paper between 100 individual blood samples tested did not seem to be responsible for a variance in excess of that introduced by the analytic procedures themselves.

The paper chromatographic behaviour of the following antioxidants has been investigated.A. Aldol-α-naphthylamine (M. P. 65100°C) C. Aldol-α-naphthylamine (M. P. 140°C min) P. A. Phenyl-α-naphthylamineD. Phenyl-β-naphthylarnineF. Di-β-naphthyl-p-phenylenediamineH. N, N'-diphenyl-p-phenylenediamineAgerire Stalite Mixture of mono and di-hepthlated diphenylamineAgrite Resin D. Polymerized trimethyl-dihydroquinolineSantoflex B. 1.2. -dihydro-2, 2, 4-trimethyl-6 phenylquinolineSantoflex BX Blend of Santoflex B (85) +H (15).After antioxidants (dissolved in acetone) were coupled with diazonium salt of aniline, reaction products were developed on paper strip (Toyo paper strip for Chromatography No.50) up to about 30 cm high. and then, after drying at room temperature, paper strip was treated with conc HCI vapor in order to observe developing spots having Specific colour.As developers a number of solvents and solvent mixtures were investigated.Acetone-benzene-water (61 : 4 : 35 by volume at 20°C) -was finally chosen as a best developer for separation and identification of antioxidants.The following paper chromatographic data were obtained on antioxidants alone. (Table 1) Table 1.Paper chromatographic data of various an-tioxidants (developed at 20°C) Developer. Aceton-Benzene-Water61 - 4 - 35(by volume at 20°C) Antioxiodants Rf × 100 Specific Colour of SpotA 90, 78 Reddish VioletC 90, 78 Reddish VioletP A 61 Bluish VioletD 48 OrangeF 98100 Pinkpale orangeH 98100 Pinkpale brownAgerite stalite 37 (5052) VioletSantoflex B 49 PinkAgerite Resin D. 060 Pale Pink diffuse zone(a) A and C showed over laped spot.(b) H and F also showed oved laped spot(c) Agerite Resin D gave diffuse zone.(d) D and Santoflex B mutually interfered.With the above chromatographic deta as a guide, further experiment was carried out in order to detect and identify of antioxidants which are present in mixed state. It was possible to separate and identify component antioxidant in A+PA+D, A+H+PA, F+Agerite resin D, C+D, F +Agedite stalite etc, Therefore, it would be expected that the proposed method provides a very convenient means for identification of antioxidant mixture. when A and C or H and F. or D and Santoflex B are not present together with in the mixture.Based on the results obtained on above-mentioned experiments, the identification of antioxidants was carried out with tread mix accelerated with MBT and tube mix accelerated with MBTS.Vulcanized Rubber (5 g) grinded by passing through rolls was extracted with acetone (10 cc) at room temp. and acetone extract was evaporated to 2cc, then it was treated by the some method as antioxidants in acetone were treated.The chromatographic treatment has been successfully applied to the vulcanized rubber. Chromatographic data obtained were quite similar to the data of antioxidants in free state.The only exception was Santoflex B which was not detected.Paper chromatographic method proposed in this experiments could be applied successfully to the identification of antioxidants either alone or in vulcanized rubber accelerated with MBT and MBTS. But more precise and general method could be developed by finding diazonium salt and developer which gives more specific spot and colour than diazonium salt of aniline and developer proposed in this experiment does.

STUDIES of the causes and mechanism of the failure of impregnated-paper insulation are commonly obscured by the burning due to the final complete breakdown. In a number of years of study of the more accessible properties of impregnated paper and their relation to stability and breakdown, constant attention has been given to the restriction of this burning and a nearer view of the beginnings of failure. Simple fuses and even rapid circuit breakers in the primary circuit of the testing transformer are of no avail. Some improvement is obtained by the use of a thyratron in the grounded lead of the sample with suitable connection to a rapid circuit breaker in the primary. But by far the best results, and indeed very complete success, have been reached by a method for detecting the first occurrence of gaseous ionization within the test specimen. This method is a development of the pioneer work of Paine1 and the subsequent applications of Arman and Starr and of Whitehead and Shaw,2 using resonance methods for following the oscillations which arise in the ionization of gas spaces in the insulation wall. New features which have been added are increased sensitivity, improved balancing of the Schering bridge for the frequency of maximum oscillations, the use of greater amplification, and a sensitive recording instrument for registering the first occurrence of internal ionization. The complete setup, as described in this paper, is called the “ionization recorder.” With this instrument it is possible to detect the beginnings of failure in a completely impregnated specimen initially free of gas spaces or voids, often to within one layer of the impregnated structure, and also to follow its growth, with interruption at any desired stage on the way to complete breakdown. So far, the instrument has been applied only to the study of the influence of paper density on dielectric strength and stability, and the comparative behavior of two types of paper and two types of oil. From the results it will be seen that a very intimate picture of breakdown and its causes is presented.

A phenomenon of adsorption of a small amount of ion by the filter paper was studied with the use of Cu++.The adsorption of Cu++ is not only caused by heretofore considered exchange of ash contained in the paper but a certain chemical combination with the cellulose, electrical or other physical adsorption is possible.Factors which have the influence on the amount of adsorption are concentration of solution, ash content, speed of filtration and temperature;especially, the influence of temperature is important from various standpoints.The liberation of adsorbed ion is difficult with the use of filter paper of high ash content and filtered at high temperature, The adsorption is increased with an increase in the concentration but these portions of increased adsorption are easily liberated by washing. Also, the change of adsorption phenomena of S2O3-- and Al+++ are studied and its mechanism is clarified.

Summary An easily made heater is described for bringing out colored spots on paper chromatograms after the detecting reagent has been applied. The device permits precise control of length and temperature of heating as well as heating the entire paper uniformly while it is clearly visible to the operator. The paper is supported on a versatile frame. Paper sheets or strips of different sizes can be accommodated.

Paper electrophoresis in combination with radioactive tracer techniques permits the investigation of the reactions of Cr+3 with SO4-2. According to our results green solutions contain invariably complexed SO4-2 groups. The kinetics of the uptake of SO4-2 was also studied at two different temperatures.

Operating variables in the use of recording ratemeters for scanning radioactive paper chromatographic strips are discussed. Bes sensitivity, and least statistical error in estimation of peak area, is obtained with a wide slit. However, wide slits give poor fidelity, that is, the shape of the record is not an accurate representation of the shape of the actual peak. Short time constnts give a record showing undesirable fluctuations due to statistical count rate variations, while long time constants give poor fidelity. Slow strip speed is required for strips of low activity. Optimal selection of operating conditions is considered from a quantitative standpoint.

Summary To study the electrophoretic properties of milk proteins under conditions as nearly similar as possible to those found in milk, a paper strip electrophoresis apparatus was designed which required small volumes of electrolyte and in which electro-osmosis could be substantially reduced. Using this apparatus, it was shown that β -lactoglobulin could be isolated from milk, crystallized, and returned to its native environment without grossly affecting its initial charge density.

A method has been developed for economically manufacturing insulated wire for telephone exchange area cable by making the paper on the wire. Further, this method has made it possible to increase the number of wires in a full sized cable by 175% over the number in use in 1914. Developments now under way indicate that suitable insulation can be made to replace certain textiles in some classes of wire and that the use of this process may therefore be still further extended in the not so distant future.

"There is hardly a question more laden with myths than the recent history of Palestine. This is true not only of the post-World War II era, but even more of the inter-war years. However, the opening to public perusal of the British government's records of the 1930's has enabled students to examine the facts and to attempt to expose certain false notions about British policy in Palestine. The creation of notions and myths is a simple matter; their refutation involves painstaking and detailed study of people, actions and policies." - Introductory paragraph. Sidney Webb, 1st Baron Passfield (Lord Passfield) served as Secretary of State for the Colonies in the Labour Government from 7 June 1929 to 24 August 1931. Between 23 and 29 August 1929 there were riots in Palestine, by then a British Protectorate, resulting in serious loss of life. As Colonial Secretary he issued the Passfield White Paper which revised the government's policy in Palestine.

The device will produce a graph from data in the form of five-track paper tape. The rate of plotting is 20 points per minute at an accuracy of up to one part in 1000. Apart from a standard ten-millivolt potentiometric recorder and tape reader, the device requires 21 transistors, 2 valves and 22 relays.

Five combinatorial pools of 28 antisera to enteroviruses were prepared for virus-typing purposes. The pools were composed in such a manner that any of the virus types could be identified by the pattern of neutralization produced by the set of pools. The virus isolate was seeded in Petri dishes with green monkey kidney cell monolayers. These were then overlaid with agarose and filter paper discs saturated with the respective serum pool were then applied to the gel. A zone of protected tissue after four days incubation was taken as neutralization. A trial with this method involving 230 coded virus isolates gave a correct typing of 219 strains. Among the pitfalls were isolates containing two viruses; the problem of mastering such situations is briefly discussed. Time studies suggest that the method described is economical in comparison with conventional typing techniques.

The employment of radio-frequencies for chemical analysis was suggested and commenced by the author in 1936. Brief mention is made of the gradual development of the “conductrimetric tube” with references to papers by him and other workers, and a new application of external electrodes and displacement currents to chromatography is presented. A circuit diagram is given in which both rectification and amplification are achieved by the use of a “Transistor”.

Practical information is given on the selection and use of protective coatings in the pulp and paper industry. The main points to be considered in the selection of any coating are relative resistance of the product to the environment, ease of application, experience under similar conditions of exposure, cost per year of the applied coating and choice of colors. Information of this kind is given for the following materials: chlorinated rubber, vinyl, liquid neoprene, epoxy-amine, asphaltic mastic and oil base paints. Also included is information concerning the resistance of these coatings to a number of acids, alkalies, acid salts, alkaline salts, neutral salts, gases and organic materials. The importance of good surface preparation is discussed. Recommendations are made concerning the application of coatings. Properties of specific coating materials are given and typical specifications listed. 5.4.5

(1955). A New Method for Determination of Bacterial Sensitivity to Chemotherapeutic Agents by Means of Paper Strips. Scandinavian Journal of Clinical and Laboratory Investigation: Vol. 7, No. 3, pp. 259-263.

A densitometric method, without the use of filters, for the determination of glycine after reaction with ninhydrin, is described and the overall error of the mehod is evaluated. The object of the study was to distinguish between DNP-Gly-Gly and DNP-Gly-Gly-G-ly. The total spot density was determined by scanning through dry paper with a photometer and measurement of the area under the curve. The maximum error commited was 10.9%, with a confidence limit of 95%, which is about half the error admissible.

A technique has been developed for studying the mechanism of filtration by viewing under the microscope the passage of contaminated oil through a thin section of filter paper. The process of filtration of several standard oil contaminants and of several crankcase oils from I.C. engines is described and illustrated.