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1 A new diagonal electrophoretic technique for determining the order of the lysine-containing tryptic peptides of a protein is described. The protein is converted into its trifluoracetyl derivative, digested enzymatically (or chemically), and the resulting peptides separated by paper electrophoresis. The paper is then treated with ammonia vapour, which re-exposes the ɛ-amino groups of the lysine residues, and submitted to a second electrophoresis at right angles to the first direction. Peptides containing lysine residues, together with the N-terminal peptide of the protein, are found to lie off a diagonal formed by all other peptides, whence they may be readily purified. A study of these peptides enables the order of the lysine-containing tryptic peptides in the protein to be deduced. 2 The technique has been successfully tested with insulin. 3 When the method was applied to porcine pepsin, the four tryptic peptides isolated were easily ordered and the carboxyl-terminal sequence of the protein shown to be Arg-Gln-Tyr-Tyr-Thr-Val-Phe-Asp-Arg-Ala-Asn-Asn-Lys-Val-Gly-Leu-Ala-Pro-Val-Ala. The three basic amino acid residues in the molecule are thus found clustering towards the C-terminus of the polypeptide chain. 4 A common ancestral gene for porcine pepsin and bovine (calf) rennin is suggested by the close homology between the C-terminal sequences of the two proteins.

Mayor Gamble has just spoken to you on water-supply from the standpoint of the health of citizens. May I discuss with you water from the standpoint of a chemist as it is required by industrial concerns as the most necessary feature of manufacturing operations, especially in the manufacture of pulp and paper, which promises to be the next great industrial development in this southeastern territory which is governed by your membership. A recent survey by the Federal Government has shown an enormous wealth of pine and semi-hardwood timber in this practically untouched region. The figures of this survey are now attracting nation-wide attention, especially since the spruce woods of the Great Lakes and Eastern States are practically exhausted and this makes necessary the importation annually of some two hundred million dollars worth of pulp and paper. About fifteen years ago when it was first proposed to manufacture kraft from southern pine it was loudly proclaimed that this was impossible, but during the intervening years there has been so rapid a growth of the kraft pulp and paper industries that the South now dominates the field with the manufacture of more than sixty percent of the national output. Now when it is proposed to use southern pine for white paper the same cry is heard about the unsuitability of southern pine. The work in the Pulp and Paper Laboratory of the Industrial Committee of Savannah has completely disproved this contention. Erroneous ideas have been held regarding our pines: first, through the use of the name "yellow" pine, which applies only to the heart, while the sapwood gives a pulp actually lighter in color than spruce; and, second, the utilization of longleaf and slash pines for naval stores

WATER is an integral part of the manufacture of pulp, paper, and paperboard. It plays a critical role in virtually every step of paper making, from the processing of pulp to the carrying of fibers to the paper-making machines. Water also is used to generate steam for power generation and for process use. Most of the water requirements are met by surface supplies (rivers and lakes) with the remainder from wells. Some mills also use city water. Since water-quality requirements for steam generation are well documented, this article will focus directly on process-water requirements and problems.

Paper chromatography has been found to be a very satisfactory method for the separation of glycerine from hexitols, pentitols, tetritols, and glycols. After separation of the glycerine on paper the glycerine is eluted from the indicated zone with water. The formaldehyde, which is a product of periodic acid oxidation, is determined colorimetrically. A suggested procedure and the results of the analyses of standard glycerine and polyhydric alcohol mixtures are presented in this paper. The results indicate that the glycerine content of the mixtures (glycerine content ranging from 15% to 100% glycerine) may be determined with an average relative precision of 0.7% and with an average recovery of 101.0%.

A reproducible paper chromatographic procedure has been developed for resolving a mixture consisting of 1-mono-, 1,3-di-, and triglycerides, cholesterol, and cholesteryl esters. The separation is accomplished, using silicic acid impregnated glass fiber filter paper as the chromatographic medium and various ethyl ether-isooctane mixtures as the solvent systems. A reagent consisting of 1:1 concentrated sulfuric acid: water has been introduced for visualizing the lipides on the chromatogram and for distinguishing between glycerides and cholesterol-containing lipides. Unsaturation in the fatty acid moiety of the mono-, di-, and triglycerides had no detectable effect on the Rf values of these substances. Fatty acid chain length did not affect the Rf of the cholesteryl esters with the solvent systems studied. Increasing the percentage ethyl ether in the solvent system caused an increase in the Rf values of each lipide not moving at the solvent front.

Despite the increasing importance of nonionic surfactants, methods for their identification have been limited to specific groups. Accordingly, a general analytical scheme for the identification of polyoxyalkylene-type nonionic surfactants was developed, which uses qualitative tests and two paper chromatographic solvent systems. This procedure differentiates among the ethoxylates of alcohols, thioalcohols, alkyl phenol, fatty acids, polyoxyethylene polyoxypropylene acids, sorbitan fatty esters, fatty amides, polyoxyethylene glycols (PEG) condensates. In addition, individual members of a class can be separated and identified. The method is applicable to a variety of detergent products and to mixtures of more than one nonionic. As little as 7 mg of a nonionic surfactant are sufficient for complete characterization.

Auxins and auxin inhibitors from tissue extracts of normal Nicotiana plants, Nicotiana glavca, N. langsdorffii and their hybrid (which spontaneously produces tumors) were separated by ascending paper chromatography with n-butanol-distilled water. An Avena curvature test was used for demonstrating growth-promoting and growth-inhibiting substances. IAA could be found in extracts of the parents and the hybrid (RF 0.75). Hybrid tissue yielded the highest amount (37.10), N. glauca tissue less (30.80), and N. langsdorffii tissue the least amount (8.50) of IAA. A second growth promoter (RF 0.35) could be separated from the tissue extracts of the parents and the hybrid, but it showed only low activity in the Avena test. Three inhibitors were present in extracts from N. langsdorffii and the hybrid at RF 0.25, 0.45, and 0.85, whereas N. glauca showed only two of them (RF 0.25 and 0.85). The inhibitor with an RF of 0.45 seemed to be identical with the acidic, benzene-insoluble "inhibitor i" of Bennet-Clark and Kefford (1953). The inhibitor (neutral, benzene-soluble) at RF 0.85 could be found in some tissue extracts of the parents and the hybrid, but showed only little activity in the curvature tests. From neutral and from acidic plant extracts within a pH range of 4.4 to 5.8 a third inhibitor with an RF of 0.25 could be separated. It seems that the high concentration of natural IAA in the hybrid is regulated by a variety of inhibitors with different specificities in the growth-regulating process. Nicotiana langsdorffii tissue has much less auxin but the same variety of inhibitors as the hybrid, whereas N. glauca tissue contains less auxin than the hybrid and only two of the three inhibitors found in N. langsdorffli and hybrid

A method is described by which unsaturated fatty acid esters can be separated and identified by reversed-phase paper chromatography. The procedure is based upon the formation of the mercuric acetate addition compounds of the esters and the detection of the compounds on the chromatograms, using the sensitive color reaction with diphenylcarbazone. The application of this technique to the analysis of the component unsaturated acids of natural fats has been examined, and tetradecenoic acid in olive oil and hexadecenoic acid in linseed oil both formerly unidentified have been detected as the minor component acids by means of the method. The preliminary investigation on the absorption spectra of diphenylcarbazone complexes derived from the addition compounds has been made to bring the method into quantitative use.

Summary Studies of the electrophoretic haemoglobin patterns in inbred strains of mice have shown two different types of patterns. In three strains, all mice tested had one type of pattern; in five, another type of pattern was found in all animals tested; and in three strains, individual mice showed either one or the other haemoglobin pattern. These data strongly indicate a genetic basis of haemoglobin differences in mice. Further work is needed to determine the exact nature of this genetic basis.

Procedures for qualitative and quantitative paper chromatography of lipides have been described in detail, together with some practical applications.

1. A reasonably reproducible method has been developed for separating lysolecithin, lecithin,, sphingomyelin, and phosphatidylethanolamine, using glass fiber filter paper impregnated with silicic acid as the chromatographic medium and 1:1 methanol:ethyl ether as the developing solvent.

A degree of reverse phase separation of triglycerides can be obtained with ascending chromatography on uncoated glass paper using a pyridine: water solvent system. The same Rf values result when silica gel coated paper is used. To extend the usefulness of this separation, the glyceryl esters are converted to methyl esters in situ using sodium methoxide. This permits, on silica gel coated paper, glyceryl ester separation in one dimension, eslatography to the methyl esters, and methyl ester separation in the second dimension. In mixtures of lipids such as serum extracts, the lipid groups may be separated in one dimension and the fatty acid methyl esters in the second dimension.

A rapid method of separating the 2,4-dinitrophenylhydrazones of C1 to C9 aldehydes by descending chromatographic system has been described. Whatman No. 1 filter paper was impregnated with ethylene glycol-methanol (1∶4, v/v), and n-heptane saturated with methanol was used as a developing solvent. Complete separation was achieved in 3 hrs. It has been shown that the method can also be used for the separation of 2,4-dinitrophenylhydrazone derivatives of ketones.

Pollution preventive measures should be built into the process when a new mill is designed; corrective measures must be taken on existing mills. For air pollution control, these measures consist essentially of enclosing all vessels that contain the black liquor from which the tall oil is recovered. Hoods are placed over storage tanks, sumps, heat exchangers, and other liquor-containing vessels. The hoods must be vented to a ductwork system that brings the off-gases to a central point for disposition. Typical devices to remove the offensive odors and particulate matter in the off-gases are wet scrubbers and incinerators. Evaporation can be used to concentrate liquids containing small amounts of contaminants to much smaller volumes and to concentrations that permit incineration. The lime kiln and recovery boiler of the typical Kraft mill commonly are used to burn the odorous gases, thus destroying the odors completely. Sometimes a separate incinerator is required. Water pollution is best prevented by careful design and operation of the various tall oil removal equipment, such as soap skimmers, level controls, and valving systems. In spite of great care in design and operation, some tall oil will enter the wastewater stream. The effluent treatment plant must be designed to take care of this residual biochemical oxygen demand load and, in some cases, provide for color reduction in the treated effluent.

A quantitative method for the determination of traces of free gossypol in oils and fatty acids was developed. The method is based on the concentration of gossypol by extraction and quantitative paper chromatography of the extract. The method is specific for free gossypol and is not subject to interferences. The new method is both accurate and reproducible. The lower limit of detection is 10 p.p.m. The method is intended primarily for p.p.m. levels but is suitable for all concentrations. With slight modifications the method is applicable to meals.

observation that unchlorinated sewage effluents fairly rich in nitrites fail to produce a color with orthotolidin. However, the period of contact in sewage testing never exceeds 5 to 10 minutes. Where nitrites are excessively high, a brownish color appears after a 10 minute contact. None the less there are no grounds which justify the 30-minute contact as specified in Standard Methods. Why the change was made remains an open question. Attention is called to the recently suggested method by R. D. Scott in the May, 1934, issue of The Journal, wherein manganese is precipitated by flocking the sample with magnesium hydrate produced from magnesium sulphate and caustic soda. In case nitrites are found, a correction (p.p.m. Nitrite N. X0.08) should be deducted from the maximum reading of apparent chlorine value. The development of color in the dark and a contact period limited to 10 minutes at 20°C. or above should, moreover, render nitrite interference of inconsequential proportions. Manganese interference is to be more seriously considered and the hydrate precipitation method developed by Scott seemed to have certain advantages over other less dependable methods including the method I have suggested, involving heating to dissipate the chlorine and determining the manganese effect (blank) by testing the boiled, cooled and diluted sample with orthotolidin. The method of reducing manganese with hydrogen peroxide, proposed by Adams and Buswell, is tricky and has to be carefully conducted to insure complete manganese reduction without destruction of the chlorine present. Regarding the ammonia-chlorine process, if for no other reason than economy, the ammonia as a general rule should be added after filtration. Fortunately, Detroit was employing prechlorination and, therefore, the false residuals were not accompanied by a breakdown in plant efficiency. In commenting on the comprehensive review of the ammonia

In the absence of the scheduled paper by Dr. Buswell, the following comments on the influence of manganese upon the orthotolidine test have been based upon published papers of Dr. Buswell and others. This literature and the paper by Mr. Hulburt are of great value in focusing attention upon the two major difficulties encountered when making the orthotolidine test. This test is of paramount importance as it provides practical and convenient means of effectively controlling the disinfection of water and sewage. The simplicity of the test, however, has been misleading and undue confidence has been placed in the results by those not accustomed to consider the chemistry of the test.

Author's Note: There seem to he some points which are not clear and some omissions which have caused confusion in the paper1 presented by the writer. Owing to the length of this paper, some data were purposely omitted for the sake of brevity. The writer wishes to thank Professor Lord for bringing these points to his attention and also for permitting this discussion of the preceding paper.

THE AMOUNT of commercial paper outstanding has more than doubled over the past three years, rising to $20.5 billion at the end of 1968 from $9.0 billion at the end of 1965.1 This rapid growth has generated widespread interest in the commercial paper market, and a number of articles dealing with the market have appeared recently.2 However, there has been no attempt to analyze the market in terms of statistically derived demand and supply functions. This paper represents an exploratory venture in this area. The first section briefly describes the relevant characteristics of the market for commercial paper. The second section outlines the theoretical and statistical approach used in the analysis. The third section presents and discusses the estimated demand and supply equations. In the final section, the model is evaluated and some of its broader implications are discussed.

In an interesting paper in Behavioral Science, Volume 12 (1967), Amnon Rapoport reported on his tests of the dynamic decision-making capabilities of a group of students. He found that the students did not perform well relative to the normative results predicted by two quantitative inventory models he had chosen. It is the purpose of this paper to point out that the wrong normative models were chosen and that if the appropriate inventory model had been picked, the students may have performed reasonably well.

This paper is de(licate(l to mn life-long friend and colleague, Doctor Henry Chandler Cowles, whose thought and enthusiasm have exerted such notable influence in the rapid (levelol)ment of American ecology throughout a third of a century. His remarkable paper on sandl-(lune vegetation and his early al)l)reciation of the dynamic relations of plant distril)ution to physiographic development came as enlightening encouragement to those who had dreamedd that it might sometime be possible to approach problems of plant distribution from the physiological viewpoint. Studies like those of Cowles furnished a logical method by which the environmental complexes of plant habitats might be usefully characterized and classified according to soils and exposure, inl terms of physiographic features that naturally pass through progressive changes with the lapse of years and centuries. Such simply descriptive terms as moraine, bluff, talus, bajada, beach, strand, lagoon, swamp, thus came to imply slowly changing systems of environmental conditions. Of course the need for a still more penetrating examination of environmental complexes was realized. It was desirable that habitat features should be described in such terms as might replresent conditions to which the indiviclual plant is sensitive, which is not immediately true of geographic or physiographic concepts; at the same time, the terms of habitat description should be susceptible of physical and chleical measurement and integration whenever suitable techniques therefor might be developed. Accordingly, there has arisen a special branch of ecology, which has been called physiological ecology. Considerable progress in physiological ecology had been made by agricultural chemists before ecology took its place among the biological sciences, and their studies on the soil relations of cultivated plants constituted an important part of the fundamental basis for the new science, although it is still sometimes forgotten that ecology must logically include cultivated forms and weeds in its purview, as well as the components of natural plant associations and other natural vegetational units. Agronomy and horticulture furnish the most readily approachable fields for fundamental ecological research, and workers in these fields early turned their attention to soil characteristics as effective environmental features. It was soon realized that the soil condi