INDUSTRIAL PROGRESS DURING THE YEAR 1874. H x 



albumin of Lieberkuhn, C 72 H 112 N 16 S0 22 ; of Loew, C 72 H 108 

 N 16 S0 22 ; or of Liebig, C 216 Il33 8 N 54 S 3 68 . Its molecular weight 

 appears to be near 1720. 



Matthieu and Urbain have examined the gaseous constitu- 

 ents of the blood, and the influences exerted by various in- 

 ternal and external conditions upon them. They show that 

 repeated blood-lettings diminish the oxygen in arterial blood, 

 because they diminish the intravascular pressure ; that the 

 chief seat of oxidation is not in the vessels themselves ; that 

 elevation of external temperature, by decreasing the osmotic 

 interchange of gases through the pulmonary mucus, dimin- 

 ishes the oxygen dissolved in arterial blood, even in spite of 

 the increased number of respirations thus caused ; that the 

 arterial oxygen varies directly as the atmospheric pressure; 

 that the arterial oxygen is directly, and carbonic acid inverse- 

 ly, dependent upon the internal temperature; that muscular 

 work increased to a limited extent arterial oxygen, a great- 

 er quantity of oxygen being consumed during work than 

 during rest ; that narcosis by morphine, and anaesthesia from 

 chloroform, by diminishing the number of respirations, dimin- 

 ished proportionately the arterial oxygen ; and that the per- 

 centage of arterial oxygen reaches its minimum about four 

 hours after a full meal, though the total quantity is in- 

 creased, but masked by the dilution. The smaller the ani- 

 mal, the less rich in oxygen is its arterial blood. Thickly 

 furred animals have less arterial oxygen than others. At the 

 extremes of life oxidation is less active, young adult blood 

 being the poorest in oxygen. 



Gobley has reinvestigated the character of Liebreich's pro- 

 tagon, obtained from brain matter, and concludes that it is 

 simply a mixture of lecithin and cerebrin, two substances 

 discovered by him long previous. The decomposition of pro- 

 tagon into glycero-phosphoric acid and neurine, observed by 

 Liebreich, the author maintains is really a change in the 

 lecithin present. ISTeurine is identical with choline discov- 

 ered in the bile by Strecker. Bourgoin describes a simple 

 method of obtaining cerebrin free from phosphorus, which is 

 founded upon its solubility in hot alcohol. 



Vogel has examined the reaction of fresh milk, and finds 

 that it is in general transiently acid ; though, since litmus- 

 solution, reddened by milk, becomes blue when exposed to 



