AKER TUBA. 21 



The first effects of the jioisou on a fish are to cause it to make 

 violent efforts to escape, jiaiii])ing- out of the water, rapidly swiui- 

 miuy aljout, etc. Then the breathing becomes laboured and there 

 is a sluggishness and uncertainty of movement ; the next symp- 

 tom is an increasing inability to maintain the ordinary position; 

 then the fish turns on its back, rises to the surface, and the breath- 

 ing becomes slower and finally ceases. When fish have reached 

 the stage of turning on their backs and rising to the surface, they 

 will, if put into fresh water, slowly revive, and after the lapse of 

 some hours appear little, if any, the worse for the experiment. 

 I have three times poisoned a fish, allowing intervals for it to 

 revive ; and it has lived in an aquarium for days or even weeks 

 afterwards. 



The poisonous principle is not, as might l)e expected, an 

 alkaloid. I at first tried the usual methods for separating these 

 substances, l)ut the residues from the exhaustion of lx)th acid and 

 alkaline aqueous solutions hj ether and chloroform did not 

 possess toxic effects. After many experiments I found that the 

 poisonous principle, for which I propose the name " tubain,"* is 

 a very brittle, reddish-brown coloured, resinous substance, quite 

 insoluble in water, paraffin oil, and benzine, but soluble in alcohol, 

 ether and chloroform. It has a specific gravity of 1-1662 ; is dis- 

 solved by nitric acid, forming a bright dragon's-blood red solu- 

 tion ; and is unacted on by strong boiling solution of carbonate 

 of soda. When heated in a glass tubes it melts, boils, and then 

 carbonizes, a brown- coloured oil condensing on the cool part of 

 the tube. It biu'ns with a large smoky flame, leaving a quantity 

 of carbonaceous ash. Fractional distillation and other means 

 would perhaps break up the resin into several distinct substances, 

 only one of which may be the virulent body ; but my very limited 

 laboratory appliances prevent me from carrying on the investiga- 

 tion further than I have done ; and I must leave to others the 

 further working out of the sul)ject. 



Tubain is most conveniently prepared by crushing up the 

 chopped root and digesting it, with little heat, for some hours in 

 alcohol acidulated with hydrochloric acid, filtering and evapora- 

 ting on a water-bath at a low tem})erature until a gummy sub- 

 stance separates. When all the spirit has evaporated and water 

 only remains, the tubain may be removed and pressed into a mass. 

 This can then he washed 1)V kneadin(>- in hot water and fiu'ther 



* The Editor of the Pharmaceutical Jouriuil says in a note : '' Mr. 

 Wray appears to have woi'ked in ignorance of Mr. Greslioff's discovery of 

 " derrid." Sec Phann. Juiiriud (3) XXI., ])p. 559-560." I was unaware of 

 it, but I separated tubain nearly five years ago, and a sample of the ])oison 

 has been e.xhibited under that name in the Perak Museum sinci; March, 

 1888. 



