May 6, 1904.] 



SCIENCE. 



.715 



The Constituents of the Venom of the 



Rattlesnake: Professor John Marshall, 



University of Pennsylvania. 



Researches on the constituents of the 

 venom of the rattlesnake are not as nu- 

 merous as those on the physiologic action of 

 the venom and those bearing upon attempts 

 to discover an antidote. The most com- 

 prehensive research on the constituents of 

 the venom of this snake was made by Drs. 

 Weir Mitchell and Reichert in 1886. Since 

 then a better knowledge of albuminous 

 substances has been obtained, newer classi- 

 fications of these substances have been 

 made and more accurate methods for their 

 separation and identification have been de- 

 vised. 



All of the substances hitherto separated 

 from the venom of this snake by the 

 methods employed were toxic. The toxi- 

 city of the substances separated is believed 

 by the author to have been due to an ad- 

 mixture of a toxic substance which was 

 precipitated with the non-toxic part as an 

 adherent material. 



By the method of separation by frac- 

 tional precipitation by means of ammonium 

 sulphate the author has been able to sepa- 

 rate the venom (using that of the Crotalus 

 adamant eus) into three fractions. Of 

 these three fractions one is toxic and two 

 are non-toxic. The first fraction of the 

 series of three was separated from the 

 venom, while in one per cent, sodium 

 chloride solution by the very slow addition 

 of saturated ammonium sulphate solution 

 ,vith constant, rapid stirring by means of 

 a mechanical stirrer until the venom solu- 

 tion was saturated with ammonium sul- 

 phate solution to the extent of 4.5/10. The 

 first fraction consists of euglobulin and 

 pseudoglobulin, is white and non-toxic. 

 The second fraction was obtained from the 

 filtrate from the first by saturation to 6/10 

 with ammonium sulphate, is yellow and is 

 toxic. Whether it is a chemical individual 



or a mixture is still under investigation. 

 The yellow coloring matter was separated 

 and is soluble in absolute alcohol, produc- 

 ing a greenish fluorescent Solution. It is 

 not a lipochrome, nor bile coloring mat- 

 ter, nor an ordinary coloring matter. It is 

 non-toxic. 



The third fraction was obtained from the 

 filtrate from the second fraction by satu- 

 rating with crystals of ammonium sul- 

 phate. It is white, non-toxic and consists 

 of albumin. 



The author was unable to detect any 

 albumoses or peptone in the venom. 



27(6 Atomic Weight of Tungsten: Pro- 

 fessor Edgar P. Smith and Dr. F. F. 

 ExNER, Philadelphia. 

 Our study, extended over a long period, 



has revealed: 



1. That it is quite doubtful whether any 

 chemists who in the past occupied them- 

 selves with a redetermination of the atomic 

 weight of tungsten have worked with pure 

 substance. Tungstic acid is prone to form 

 ' complexes. ' It was found that if the acid 

 contain no iron, for instance, but be di- 

 gested with acids, *. e., hydrochloric or 

 nitric acid, in which iron is present, the 

 latter will enter the tungstic acid. Iron 

 and manganese are eliminated from the 

 acid with the greatest difSculty. In the 

 earlier M'ork there is no evidence of their 

 removal; neither do we discover that 

 vanadium and phosphorus had been con- 

 sidered as present, yet in purifying am- 

 monium paratungstate by recrystallization 

 alone it was found that the tenth recrystal- 

 lization showed vanadium. 



2. The slimy, greenish or bluish-white 

 masses helieved to be 'para-tung-states' be- 

 cause of their great insolubility are prob- 

 ably 'complexes.' 



3. The use of pure sodium carbonate 

 (two per cent.) to dissolve tungsten tri- 

 oxide gives an excellent means of ascertain- 



