452 



SCIENCE 



[N. S. Vol. XXV. No. 638 



longer the two corresponding residuals 

 might have been slightly larger. 



W. S. ElCHELBERGER 



U. S. Naval Obseevatoet 



THE NEW YORK MEETING OF SECTION 

 OF THE AMERICAN ASSOCIATION FOR 

 THE ADVANCEMENT OF SCIENCE 

 AND THE THIRTY-FIFTH GEN- 

 ERAL MEETING OF THE 

 AMERICAN CHEMICAL 

 SOCIETY— II. 



BIOLOGICAL CHEMISTEY 



"Wm. J. Gies, Chairman 

 The Rational Conversion of Energy: J. E. 



SlEBEL, Jr. 

 The Thermodynamics of Nutrition: J. E. 

 SlEBEL, Jr. 



The Effects of Magnesium Sulphate upon 

 Seedlings: Gertrude Burlingham. 

 From extended experiments upon the 

 growth of seedlings in dilute solutions of 

 magnesium sulphate, it was found that 

 while it is usually toxic in strengths greater 

 than ilf/8192 (0.003 per cent.), it produces 

 decided stimulation in ilf/16384, reaches a 

 maximum stimulation at dilutions from 

 M/32768 to M/131072 (0.00075 per cent, 

 to 0.00018 per cent), then beyond this 

 point gradually diminishes in action. The 

 point of toxicity and of greatest stimula- 

 tion varies with the type of seedling. Both 

 the plumule and the roots attain greater 

 growth in these favorable dilutions of 

 magnesium sulphate and in the control of 

 distilled water, and often the lateral roots 

 develop two or three days sooner. While 

 growth in the control practically stops at 

 the end of one week, it continues from 

 four to five weeks in the magnesium sul- 

 phate cultures. Two parallel series, one 

 magnesium sulphate and control, the other 

 calcium nitrate and control, in dilutions 

 from M/8192, M/16384, etc., to M/262144, 

 showed that calcium ceases to be stimula- 

 ting in the dilution in which magnesium 



loses its toxicity and produces maximum 

 stimulation; in M/32768 magnesium sul- 

 phate the root growth is eight times that in 

 calcium nitrate. In every instance after 

 the renewal of the solutions, growth was 

 accelerated in the magnesium cultures, 

 while there was little change in the control. 

 Seedlings allowed to grow for several weeks 

 in a dilution of magnesium sulphate which 

 was at first slightly toxic, finally developed 

 strong lateral roots and attained a root 

 growth far beyond the control. These re- 

 sults show conclusively that magnesium 

 sulphate in proper dilution is beneficial to 

 the growth of seedlings, and that any in- 

 hibitory effects are due to the presence of 

 excessive amounts, thus controverting 

 Loew's theory that magnesium salts when 

 alone in solution are always injurious to 

 plant growth. 



Chronic Arsenical Poisoning and the Dis- 

 tribution of Arsenic in the Animal Or- 

 ganism: Wm. D. Harkins. 

 In copper smelting regions areenic is 

 likely to be a constituent of grass, hay, and 

 all the organs of animals. Grass has been 

 found to contain as high as 1,500 parts of 

 arsenic trioxide, and the ulcers in the noses 

 of horses as high as 1,000 parts per million. 

 0.362 Gram of arsenic trioxide killed a 

 sheep in eight days, 0.123 gram of sodium 

 arsenite killed a sheep in thirty-three days 

 with thirty-one pounds loss of weight, and 

 0.055 gram in sixty-nine days with ten 

 pounds loss in weight. 



On Proteose Fever: R. B. Gibson. 



Fever has been considered to result from 

 the injection of prepared proteoses and of 

 bacterial endo- and extra-cellular proteose- 

 like substances, especially as albumosuria 

 is often observed in septic and aseptic 

 fevers of experimental or natural origin. 

 As yet no observations have been made 

 with proteoses prepared from highly puri- 

 fied or crystalline proteids. Pepsin-HCl 



