374 



SCIENCE 



[N. S. Vol. LI. No. 1319 



protein nitrogen compounds which give much 

 trouble in the defecation of the juice for sirup. 

 1-leucin, d-l-asparagin, glutamin and aspartic acid 

 have been identified. The acids found in the juice 

 are aconitie, citric, oxalic, tartaric and malic. The 

 hexoses decrease, and sucrose increases, as matur- 

 ity approaches. In northern-grown cane the suc- 

 rose-hexose ratio is considerably lower than in 

 southern-grown cane, and the total sugars are also 

 much less. During the pre-maturation period the 

 sorghum plant lays down a protein-cellulose frame- 

 work, which is filled in with carbohydrate during 

 the final maturation period. This carbohydrate is 

 starch in the case of the seed head, and sucrose in 

 the stalk. The removal of the seed heads prior to 

 maturity hastens the production of sucrose in the 

 stalk, but does not affect the total amount formed. 

 The physiology of germinating Juniperus seeds: 

 D. A. Pack. (By title.) The Juniperus seed fails 

 to germinate when put under ordinary germinating 

 conditions. The changes, that prepare this seed 

 for germination, are brought about by storing at 

 5° C. These changes are characterized as follows : 

 an early and complete imbibition of water; a 

 slow increase of the H+ concentration and total 

 acid; evident changes in the stored food material; 

 very slight increase of the respiration and oxidase 

 activity; slow enlargement of the embryo with the 

 development of internal stress; steady decrease in 

 the viscosity of the seed coat; marked increase in 

 catalase activity; and an increase in the vitality 

 of the seed. A good percentage of germination 

 follows at once upon the completion of these 



The iioohemist on the hospital staff: Fred- 

 erick S. Hammett. The paper pointed out the 

 advantage which would accrue to medicine if the 

 hospital biochemist were regarded as a coordinate 

 member of the hospital staff, a specialist in a spe- 

 cial field, rather than as a mere technician who 

 makes routine analyses. 



A spectrographie study of certain iiochemical 

 color reactions: 6. L. Wendt and T. Tadokoro. 

 (By title.) 



Studies of wheat flour grades. I. Electrical con- 

 ductivity of water extracts: C. H. Bailey and F. 

 A. Collatz. (By title.) The studies previously 

 reported by one of us (Science, Vol. 47, pp. 645- 

 647) were continued, and it was found that time 

 and temperature of extraction affected the elec- 

 trical conductivity of water extracts of wheat 

 flour. The conductivity increased with the period 

 of extraction, the proportional increase being 



greater when the extraction was conducted at lower 

 temperatures, and also with the lower grades of 

 flour. The relative conductivity increased as the 

 temperature of extraction was raised above 0° 

 until 60° was approached, when it began to di- 

 minish. A standard procedure was adopted for 

 comparing a number of flours containing from 

 0.40 per cent, to 2.38 per cent, of ash. The flour: 

 water (1: 10) mixture was held at 25° for ex- 

 actly 30 minutes, centrifuged, and the conductivity 

 of the clear liquid determined by means of a dip- 

 ping electrode constructed for the purpose. 

 When examined in this manner a remarkably close 

 parallelism was observed between the conductivity 

 and the ash content. 



Studies of wheat flour grades. II. Buffer values 

 of water extracts: C. H. Bailey and Anna Peter- 

 son. (By title.) The hydrogen-ion concentration 

 of water extracts of various grades of wheat flour 

 varies between rather narrow limits. Flours with 

 an ash content of 0.45 per cent, yielded an extract 

 (prepared by extracting a 1: 5 mixture for 60 

 minutes at 25°) of Ph = 6.1, while the extracts of 

 flours containing from 1.2 per cent, to 1.6 per cent, 

 of ash had a Ph = about 6.4. The buffer values of 

 the extracts of these flours varied greatly, how- 

 ever. Thus the addition of 10 c.c. of N/50 NaOH 

 increased the Ph of patent flour extracts 3.3 (i. e., 

 to about 9.4) while the extract of lower grades was 

 increased in some instances only 0.6 to .9 in terms 

 of Ph. The increase in Ph is thus dnversely pro- 

 portional to the ash content, and the ratios are 

 quite exact. The buffer value of extracts uni- 

 formly prepared is indicative of the grade of 

 sound flours milled from normal wheat. 



The preparation of certain monooarioxylic adds 

 from sugars: I. K. Phelps and W. T. McGeorqe. 

 Charles L. Parsons, 



SCIENCE 



A Weekly Journal devoted to the Advancement ot 

 Science, publishing the official notices and pro- 

 ceedings of the American Association for 

 the Advancement of Science 



Published every Friday by 



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LANCASTER, PA. GARRISON, N. Y, 



NEW YORK, N. Y. 



Entered in the pott-«ffic* at Lancaster. Pa., m» mcoim] clan natlev 



