336 ESSAYS anp OBSERVATIONS 
caufe, after feparating the flernum from 
the ribs, and thus cutting off all céromu-: 
nication between it and the fpinal mar- 
row, the-mufcles attached to it, could be 
no more affected by the opium, which 
had been injected into the cavity of the 
abdomen; while the heart and other muf- 
cles, whofe communication, by means of 
the nerves, with the brain and fpinal mar- 
row, was intire, continued to be expofed 
to its action ? ; 
(k) As Dr Langrifh has obferved, that 
the diftilled water of laurel-leaves injected 
into the cavity of the abdomen, kills dogs 
fooner than when it is taken into the fto- 
mach *; fo N° 21. and 23. compared with 
N° 22. fhew that opium injected into the 
ftomach and great guts of dogs, does not 
produce either fuch fpeedy or powerful 
effets, as when thrown into the cavity 
of the abdomen, And N° 6. compared 
with N° ro. fhews, that a folution of o- 
pium applied to the abdominal mutfcles, 
does not kill frogs fo foon as when all the 
vifcera 
* Phyfical experiments on brutes, p. 64, 
