August 22, 1902.] 



SCIENCE. 



287 



the effects of the urea and other organic 

 bodies being but slight. In a lengthy- 

 series of tests the variation in conductivity 

 throughout the day is determined. The 

 whole of the day's urine was collected in 

 three-hour periods and in each portion the 

 conductivity was found, and also the 

 amount of chlorine and urea. By calcu- 

 lating the chlorine as sodium chloride and 

 estimating the conductivity of this, by sub- 

 traction the element of the conductivity due 

 to other salts is obtained. This becomes a 

 factor of some importance in the study of 

 body metabolism at different periods 

 through the day. The urines of different 

 individuals are compared. 



Gluten Feeds, Determination of Fat and 



Acidity: Edwakd Gudeman. 



Drying corn gluten feeds in hydrogen, 

 vacuum or air modifies them sufficiently 

 to give low results for the percentage of 

 fat. It increases the acidity of the ex- 

 tracted fat. Gluten meals containing 5.16 

 per cent, fat before drying gave 3.56 after 

 drying. Acidity of fats extracted before 

 drying, 5-15 per cent., and acidity of fats 

 extracted after drying 20-40 per cent. 

 Acidity of feed materially influenced by 

 the indicators; methyl orange neutral to 

 alkaline, rosolic acid 6-7 acidity and phe- 

 nolphthalein 11-12 acidity. Acidity of 

 feeds is due to acid salts and is no criterion 

 of quality of feed or of raw materials from 

 which they were made. 



A Novel Constant High Temperature Bath : 



Charles Baskeeville. 



A drawing was shown of the bath, which 

 is essentially an iron water-bath with as- 

 bestos jackets wherever exposed and a 

 double cover, one being copper. An iron 

 float, provided with depressions to fit plat- 

 inum crucibles, which rests upon the fus- 

 ible alloy, is held in position by copper 

 springs reaching to the copper flange of the 

 bath. A cylindrical handle rises verti- 



cally from the center of the float; just 

 above the asbestos cover the iron cylin- 

 der is sufficiently large to contain a ther- 

 mostat by which the gas is controlled. 

 The two covers are provided with slits that 

 they may be placed and removed when the 

 float is in position. A brass sheath con- 

 taining a thermometer graduated to 550° 

 C. passes through the covers, projecting 

 within one of the crucible depressions. The 

 bath is being used in redetermining the 

 atomic weight of thorium according to the 

 method of 0. Kriiss, and was paid for in 

 part by a grant from the American Asso- 

 ciation for the Advancement of Science. 

 (Will appear in the Journal of the Ameri- 

 can Chemical Society.) 



Quantitative Blowpipe Analysis hy Bead 

 Colorations: Joseph "W. Richaeds and 

 Walter S. Landis. 



Dr. V. Goldschmidt, of Heidelberg, Ger- 

 many, has constructed a plate of colored 

 glass, showing the various tints character- 

 istic of the metallic oxides when dissolved 

 in borax bead or salt of phosphorus bead, 

 in the oxidizing or reducing flame. These 

 tables are obtainable from Stoe, Mechan- 

 iker, Heidelberg, and therefore are now 

 available as standards for bead colorations. 

 The first part of the work consisted in de- 

 termining the percentage of metallic oxide 

 present in the beads when presenting the 

 color of the glass representing them on the 

 plate. This we have determined for Fe, 

 U, Cr, V, Mo, Cu, Co, Ni, Mn, Ti and W. 

 These being known, the substance to be 

 tested is weighed off, and enough taken 

 up in a bead to give the standard color. 

 The bead is then weighed, and from the 

 known percentage required to give this 

 color, the amount of coloring oxide is 

 These being known, the substance to be 

 being determined by a second weighing, 

 the percentage of metallic oxide in it is 

 known. The accuracy varies from one to 



