METHODS ADOPTED IN EXPERIMENTING <>N KAHHITS. H7 



iiR'aii> of an ordiiuirv syrinj^c aiul a piero of rublxT tubing-. The tube 

 was well oiled and shoved gvntiv into the aniniaFs stomach, connection 

 made with a syringe, and its contents injected into the stomach. In 

 every case the extracts represented a detinite quantity of the fresh 

 plant. If the first injection produced no characteristic symptoms 

 within a half hour, a larger dose was given, and this operation repeated 

 until the true character of the plant was established. When the fatal 

 dose was determined other animals were given an equal quantity and 

 thv. effect of antidotes, especially of the permanganate of potash, was 

 determined. In view of the large number of plants to be tested, only 

 two extracts, one aqueous and one alcoholic, were used in most cases, 

 A more satisfactory examination would iiave been made if we had used 

 about a half dozen of the more common solvents, but lack of time 

 would not permit this, and it was thought, moreover, that working as 

 we did, with fresh, green material, the toxic substances would be more 

 soluble in water than if the dried plants had been used. The aqueous 

 extract was tried iirst, then the extract from the well-pressed residue 

 used for obtaining the aqueous extract, was given. The poison in the 

 latter case being in a solution of 50 per cent alcohol, it was necessarj^ 

 to dose other rabbits with equal quantities of alcohol in order to note 

 the difference in eft'ect which was due to the poison. The alcohol given 

 with the poison may in some cases have acted as a partial antidote in 

 modifying the symptoms, and in some cases it may have increased the 

 intensity of the action. ])ut as the amount given was in almost every 

 case very small it could have had but little effect on the ultimate action 

 of the poison, the real point at issue. 



Care svas o])served in most of the experiments made to use fresh 

 unwilted plants of a detinite stage of growth and to cut up a weighed 

 quantity lineh" in a sausage grinder, saving all of the juice and extract- 

 ing this material for al)out twelve hours with a detinite weight of water 

 or 50 per cent alcohol, in no case apphnng a higher temperature for 

 the extraction than that normal to the human body. The aqueous 

 extracts were used wnthin a few days after their preparation in 

 order to preclude changes which might be brought about by molds, 

 which in some cases attacked the extracts within three or four days. 

 No difficulty was experienced in keeping the alcoholic extracts in an 

 uncontaminated condition. 



A few of the extracts were, on account of the short time at our dis- 

 posal, tested hypodermically on the rabbits. In these cases it was our 

 object simply to discover whether the plants were poisonous or not, 

 and due allowance was made for the difference in the method of intro- 

 ducing the poison into the system. As is well known, all poisonous 

 substances are more energetic when injected under the skin than when 

 taken into the stomach. Some, such as dilute mineral acids and the 

 venom of certain poisonous snakes, are practically inert when taken 



