182 Dr. Oliver on the Prussic Acid. 
during the night, the air bubbles might have been equally 
diffused through the ice, but, as the nights(according to the 
usual course of things) are marked by a rather sudden and 
commonly by a considerable increase of cold, the layer of 
water afiaer to congeal, was made suddenly to evolve the 
dissolved air, and this, from its levity, rising rapidly through 
the as yet fluid water, necessarily collected with considera- 
ble regularity, just at the bottom of the oe —— layer 
of ice, but still completely within the new 
vit was observable that the layers of air bubbles were well 
defined and regular on the upper side, but irregular on the 
lower—many bubbles being below the general level, and 
appearing to have been arrested before they had time to 
arrive at the upper surface of the water. 
: MEDICAL CHEMISTRY. 
i= XXVI—On ‘the Hybrocganie or Prins Acid, by 
at B. Lyxve Otiver, M.D. of Salem, Mass. 
Tnsanum quiddam esset, et in se contrarium, existimare ea, que. adhuc 
nunquam facta sunt, fieri posse nisi per modos adhuc nunquam tentatos. 
Baco Organ. Aphor. V1- 
; TO PROFESSOR SILLIMAN, 
tee Sir, 
Havine read in your excellent Journal of Science and 
rts, a very interesting paper on the Prussic Acid, in which 
on the trial they may have made with this active agent; I 
now beg leave to avail er of it, and hope that you will 
ity 
than nine years since I gave an attention 
to this subject,* nor did I then know, that the Prussic acid 
* ib Dr--Thatcher’ 8 interesting ding! pow, aalit ed, Observations on Hydro- 
hobia, | fats cers Th chy urel is the same 
of it t has bee 1 * is 5 ‘a see : 
icp ee Dr. B. ine Oliver fg has recently mat 
