July 7, 1922] 



SCIENCE 



25 



and amide 2.81 per cent, in the high protein and 

 52.15, 1.53, 8.21 and 6.25 respectively in the low 

 protein corn. The zein is higher yet in high pro- 

 tein popcorn, averaging 57.24 per cent. 



Errors in the determination of fat in cream: 

 E. G. Mahin and E. H. Cakr. The use of hydro- 

 carbon oils, non-miseible with butter fat, for elim- 

 inating the upper meniscus in the necks of Bab- 

 cock bottles has become quite natural. More 

 recent experimental results in the Purdue labora- 

 tory have shown that in the hands of the ordinary 

 dairy tester this results in readings averaging 

 about 0.5 per cent, lower than when the bottom 

 of the meniscus, obtained without added oil, is 

 used. As the latter has formerly been shown to 

 be about 0.5 per cent, lower than is given by the 

 gravimetric method, the use of such oils (such as 

 "glymol") ordinarily results in a loss of about 

 1.0 per cent, of fat for each test. Ten large 

 ereameries in Indiana averaged 100,000 cream 

 tests in 1917. Upon the assumption that each 

 test represented a five-gallon lot, this represented 

 approximately 500,000 gallons of cream. An ex- 

 perimental error of 1.0 per cent, in the fat deter- 

 mination therefore meant a loss to the producer of 

 more than 40,000 pounds of butter fat, if the 

 "glymol" method was used in all cases. The 

 Talue of this fat was approximately $20,000. The 

 reading error has been found to vary according to 

 the method of adding the oil. If the latter is 

 added slowly and carefully, little or no error 

 occurs. If the oil is run in rapidly, as is ordi- 

 narily the case, it momentarily sinks into the 

 liquid butter fat, and as it rises it carries some 

 of the latter upon its surface, thus decreasing the 

 length of the residual fat column. It is conclu- 

 sively shown that the method is not safe in the 

 hands of the average dairy tester, but the use of 

 amyl alcohol for this purpose, substituted for 

 hydrocarbon oils, gives reliable results in all cases. 

 The commercial purification of phosphoric acid 

 by crystallization: William H. Eoss, G. B. 

 DuBGiN and E. M. Jones. Commercial phosphoric 

 acid contains among other constituents such 

 poisonous impurities as lead, arsenic and fluorine. 

 Acid intended for use in the manufacture of 

 foodstuffs must therefore be treated for the elim- 

 ination of these materials. This is done, at pres- 

 ent, by precipitation with the aid of suitable 

 reagents. The effectiveness of this method is 

 limited by the solubility of the precipitate in the 

 acid. It has been found that by concentrating 

 phosphoric acid, at a temperature below 105°, to a 

 specific gravity of 1.85 at 20° and inoculating 



with a crystal of phosphoric acid, the greater part 

 of the acid will crystallize, leaving the impurities 

 in the mother liquor. The crystallization may be 

 repeated by eentrifuging, melting the crystals at 

 a temperature above 40° C, cooling to ordinary 

 temperature, adding water to bring to a specific 

 gravity of 1.85 and again inoculating. Two or 

 even one crystallization will usually be sufficient 

 for acid of commercial quality, but by repeated 

 crystallizations acid of any desired degree of 

 purity may be obtained. When phosphoric acid 

 is prepared by the volatilization process and col- 

 lected in a Cottrell precipitator, it is usually of 

 such a concentration that it may be crystallized 

 with little or no initial concentration. The 

 crystallization method is therefore especially 

 adapted to the purification of volatilized phos 

 phorie acid and experiments on the eommercia 

 development of the method are now in progress 



Do velvet ieans contain vitamin B? E. E. 

 MiLLEE. Fourteen pigeons were fed on an exclU' 

 sive diet of polished rice until pronounced symp' 

 toms of polyneuritis appeared. Seven of these 

 were restored by feeding each five grains of corn. 

 The other seven were fed five velvet beans each 

 with the result that all were improved temporarily, 

 but all died "within two to six days. Of another 

 group of six which were fed polished rice, two 

 died, apparently from starvation. Of the four 

 brought down with polyneuritis, three were com- 

 pletely restored by administering to each 0.5 

 grams of an alcoholic extract of velvet beans and 

 one was partially restored. This amount of ex- 

 tract represented three beans of average size. The 

 more favorable results obtained with the second 

 group is probably due to the greater availability 

 of the vitamin and is believed to show that the 

 velvet beans contained a fair amount of vitamin B. 



The occurrence and composition of some Ala- 

 bama phosphates: B. B. Eoss. 



The mineral requirements for the nutrition of 

 wheat during the seedling phase: H. H. King and 

 M. G. Sewell. Wheat was grown in sand cul- 

 tures, the nutrient solution consisting of KH^PO , 

 Ga(NO ) and MGSO and the concentration of 

 the salts in each pot having a calculated osmotic 

 value of 1.00 atmosphere but differing by incre- 

 ments of Ys in salt proportions. The pots were 

 arranged in duplicate triangles of twenty-one pots 

 each. The experiment was carried through the 

 seedling phase of five weeks' length. Solution 

 E S^ which was chosen as best consisted of 

 KH^PO^, Ca(NOj), and MgSO^ in the following 

 proportions, 3:2:3, and the respective partial vol- 



