The examination of a number of food products recently has revealed that propylene glycol and certain esters of the hydroxy benzoic acids have been used as preservatives. The present research was undertaken for the purpose of preparing a series of glycol benzoates, which might be used as food preservatives.Only a few of the glycol benzoates have been described in chemical literature. Wurtz (1) by whom ethylene glycol was discovered, prepared and described ethylene glycol dibenzoate before 1860. Propylene glycol dibenzoate was first prepared in 1871 by Friedel and Silva (2), by treating silver benzoate with propylene bromide dissolved in anhydrous ether. Trimethylene glycol dibenzoate was

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The purpose of this experiment was to study by means of the split-litter technique the effect of vitamin B* (G) deficiency in the diet of nursing rats upon their maze-learning ability.In the first article of this series (3) the writers reported an experiment which dealt with the effect of B-complex (Bi + B s ) deficiency when the split-litter technique was used. There it was shown definitely that such a deficiency in the diet of nursing rats adversely affected the acquisition of a maze habit at the age of seven weeks, the retention of this habit for five weeks, and the acquisition of a new habit immediately after the retention test.The situation in the present experiment represents an exact duplication of that of the first experiment in all respects except in the nature of the vitamin deficiency. The same water-maze was used when the rats were seven weeks old. The retention of the first maze habit was tested when the rats were three months old; and immediately afterwards they learned the second water maze. Since the details of the apparatus and procedure are given in the first report (3), they will not be repeated here.The deficient diet consisted of the following ingredients and was adequate in all nutritional factors except vitamin B 2 (G). percent Purified casein 18 Butter fat, water and curd free 8 Cod liver oil • 2 (Cmtiuded on patu tf)

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While experimenting with crystal violet bile media for use in water analysis, it was thought that some information could be obtained by testing the growth of anaerobes in media containing crystal violet and bile. An ideal medium for the detection of pollution in water supplies would be, of course, a medium which would prevent the growth of all bacteria except members of the colon group. This, however, is far from possible. B. welchii and other anaerobes are responsible for many false presumptive tests in waters. This fact was first reported by Frost (1906) in 1906. Many investigators have observed this condition in recent years. The question arose as to whether crystal violet bile broth would be effective in preventing the growth of anaerobes. Apparently this subject has not been investigated in regard to water analysis as no reference could be found in the literature. Hall and Ellefson (1918) (1919) were the first to call attention to the fact that gentian violet, when added to lactose broth, would eliminate the false presumptive test due to anaerobes. They found that one part in 20,000 was effective in eliminating all gas-forming anaerobes. Wagner and Monfort (1921) confirmed the work of Hall and Ellefson. EXPERIMENTAL Lactose broth was prepared and varying amounts of crystal violet and bile were added. The strength of the lactose and peptone was 1 per cent each. The pH value of all media was 117