' SUBJECT INDEX 



527 



Proteases, catheptic, by Linderstr0m- 

 Lang-Holter method, 303 

 peptic, by Linderstr0m-Lang-Holter 



method, 303 

 tryptic, by Linderstr0m-Lang-Dus- 

 piva method, 304 

 by Weil method, 306 

 Protein reactions, brief survey, 56 

 Proteins, arginine and arginine-con- 

 taining, chemical staining meth- 

 ods, 56 

 Proteolytic enzymes, by acidimetric 

 acetone method, 303 

 by alkalimetric alcohol method, 304 

 by formol method, 306 

 by titrimetric methods, 302 

 Prussian Blue test for ferric iron, 20 

 Purines, chemical staining methods, 

 72 



Quartz torsion balance. See Balances. 

 Quinalizarin reagent in determination 

 of magnesium, 18 



R 



Rachele, device for drawing micro- 

 pipettes, 176 



Radioactive elements, detection by 

 radioautography, 153 



Radioactive isotopes as- tracer ele- 

 ments, 154 



Radioautographs, 156 



Radioautography, 153. See also 

 Radioautographs and under spe- 

 cific compounds to be determined, 

 advantages, 156 



Belanger-Leblond preparation of 

 photographic emulsion for use in. 

 157 

 limitations on radioactive isotopes 



studied, 153 

 role in use of tracers 153 



Rafalko modification of Feulgen re- 

 agent for detection of chromatin 

 elements, 65 



Ralph method for hemoglobin, 62 



Ramsay method for iron, 278 

 Ramsay titanometric method for iron, 



removal of copper, 279 

 Rapkine nitroprusside test for sulf- 



hydryl and disulfide groups, 36 

 Reaction rate, mea.surement by dila- 



tometric techniques, 417 

 "Reduced weight," definition, 421 

 by dilatometric techniques, 420 

 Reducing substances, colorimetric de- 

 termination by capillary tube 

 technique, 210 

 Reducing sugars. See Sugars. 

 Redactor, in chemical techniques, 170 



for estimation of iron, 170 

 Respiration, use of Capillary diver 



technique in, 382 

 Respiration rates, factors governin,q; 

 choice of capillary diver for, 392 

 Respirometer, differential. See Dif- 

 ferential respirometer. 

 open-tube, 319 

 Respirometry, optical lever. See Opti- 

 cal lever respirometry. 

 Rhodanine, p-dimethylaminobenzyli- 

 dene, for localization of copper, 

 23 

 for localization of mercury, 24 

 of silver, 26 

 Riboflavin, chemical staining methods, 

 43 

 localization by direct observation of 

 fluorescence, 104 

 by spectroscopic analysis of fluor- 

 escence, 109 

 by Lowry-Bessey method, 440 

 by microbiological techniques, 439 

 factors influencing determination. 

 439 

 Ribonuclease, use in Dubos-Brachet 

 method for detection of ribonu- 

 cleic acid, 66 

 Ribonucleic acid, Dubos-Brachet 

 method, 66 

 Turchini, Castel, and Kien method 

 for differentiation from thymonu- 

 cleic acid, 66, 69 

 Roberts method for localization of 



gold, 27 

 Roe-Kuether method for ascorbi-o 

 acid, 245 



