332 ANNUAL OF SCIENTIFIC DISCOVERT. 



nux vomica, all of which go to confirm him in ascribing to cauteriza- 

 tion a power even greater than that commonly allowed it. " From 

 these experiments it results that the immediate amputation or destruc- 

 tion of the living portion with which the extract of nux vomica has 

 come in contact, has the power of preventing the bad effects of 

 the poison, even when it has been in contact for some time." The 

 author is aware that there is considerable difference between the virus 

 of animals and the substance used by him, with reference to their 

 direct and remote effects, but things that every one must admit that 

 here is a great analogy between them. He is of the opinion, that in 

 both cases the poison remains in the bitten part for a considerable time 

 before it is transmitted to the rest of the body, and that cauterizing 

 should be adopted in all cases where a poisonous bite is even sus- 

 pected. 



INVESTIGATION RESPECTING THE CAUSES WHICH PRODUCE A 



BLISTER. 



BY a series of experiments made at the Lawrence Scientific School, 

 Dr. Breed has shown that a certain degree of pressure may entirely 

 counteract the blistering effect of cantharides, and also that produced 

 by steam of 212, or boiling water. It has likewise been demonstrat- 

 ed, that cutaneous evaporation is not essential to the formation of a 

 blister. Editors. 



THE POISON OF SPIDERS. 



AT a recent meeting of the Linnsean Society, Mr. Blackwall com- 

 municated a paper on the alleged power possessed by spiders of poi- 

 soning whatever they bite. He states, that in the summer of 1846 he 

 commenced an experimental investigation of the subject, the particu- 

 lars of which he communicates, arranging his experiments under four 

 distinct heads, corresponding to the objects upon which they were 

 made, namely, the human species, spiders, insects, and inanimate 

 substances. We can only give his results, which are as follows. 

 First, as regards the effect of the bite of spiders upon the human spe- 

 cies. Mr. Blackwall states, that the conclusion properly deduced 

 from his various experiments is, that there is nothing to apprehend 

 from the bite of the most powerful British spiders, even when inflict- 

 ed at a moment of extreme irritation, and in hot, sultry weather, the 

 pain occasioned by it being little, if#ny, more than is due to the lacer- 

 ation and compression which the injured part has sustained. Under 

 the second head, the observations were made on both the male and fe- 

 male of various spiders, and the result is, that extensive mechanical 

 injuries commonly prove fatal to spiders, whether received in conflicts 

 or otherwise ; but the experiments supply no evidence indicating that 

 the fluid emitted from the fangs of the spider possesses a property 

 destructive to the existence of animals of that order, when transmitted 

 into a recent wound. 



