216 Mr Murray on Hydrocyanic Acid and Opium, 



was convulsed. Strong ammonia was dropt into the animal's 

 mouth, and it was repeatedly wetted with a sponge dipt in 

 ammonia. It almost instantly revived, and even licked re- 

 peatedly the finger which sometimes applied the ammonia, ap- 

 parently quite sensible of the instant and continued relief it af- 

 forded. The animal effectually recovered. Its lips were ex- 

 coriated by the ammonia. 



Conscious of the complete antidote to this formidable poi- 

 son found in ammonia, I took a quantity of hydrocyanic acid, 

 sufficient to produce violent head-stupefaction, &c. but diluted 

 ammonia afforded me instant relief. I occasionally applied it 

 to the olfactory organs, and bathed the forehead. 



Since hydrocyanic acid has been introduced into our Phar- 

 macopoeia, and employed in phthisis pulmonalis, and acciden- 

 tal poisoning may be anticipated, it is of much moment to 

 know an effectual barrier to its virulence ; and such is my 

 complete conviction of the antidote, that I would feel no he- 

 sitation whatever in taking a quantity sufficient to prove fatal, 

 provided there stood by a skilful hand to administer the re- 

 medy. 



It is admitted, that morphia is the active principle in opium. 

 Morphia dissolved in alcohol, in which, however, it is sparing- 

 ly soluble, produced on the sciatic nerves of a prepared frog 

 effects analogous to those of the tincture of opium. Acetic 

 acid restored the voltaic excitability. 



The sciatic nerves were moistened with superacetate of mor- 

 phia, but the excitement was the same as if none had been ap- 

 plied. 



A frog's head and abdominal viscera were steeped in super- 

 acetate of morphia, but ,the voltaic action remained unhinged. 



Haifa drachm of superacetate of morphia was given to a 

 young rabbit, but no apparent derangement of its healthy 

 functions took place. It rather seemed to act as a stimulus to 

 appetite. 



These experiments pointed out acetic acid as the counter- 

 poison to opium ; and, from its volatile properties, and other 

 characters in which it differs almost essentially from acetic acid, 

 having no affinity with it, except in an acid character, and 

 having much of the features of an ether, I am of opinion that 



