bia ig 
7 
an! 
: 
ES 
4 _ glass, an 
_ of amalgam 
P _* — ‘ » . 
a. * spar —— and-Calcium.- _ 295 
they ‘extended may %e learned. froth the following loonions 
from the > Bakerian- lectures of that célebrated chemist. In. 
tence to his efforts to isolate the radical in question, the distin- 
| lecturer mentions “that to obtain a complete decomposi- 
extremely difficult, siice nearly a red heat was required, 
aihst #* red h the: bases ofthe earths acted upon the 
eo ygenated. When the tube was large in pro- 
portion to the quantity of amalgam, the vapor of naphtha furnish- 
ed oxygen Sufficient to destroy a part of the basés ; and when a 
small tube was employed, it was difficult to heat the part used as 
aretort sufficiently to drive the whole of the mercury, from the 
base without raising too highly tlie temperature of the part serv- 
ing for a receiver so as to burst the tube.” ‘* When: the quantity 
bout fifty or sixty grains, I found that the tube 
could not be conveniently less than one-sixth of an inch in di- 
ameter, and of the capacity of about half aeubic inch. In conse- 
er of these difficulties, in a multitude of trials, I had few 
uccessful results; and in no case. could I be absolutely certain 
that there was not a minute portion of mercury still in combina-_ 
tion with the metals of the earths.’”* 
The observations are more than confirmed by my v-oupacienoly 
which leads me to the conviction that the removal of the mer- 
cury is not to be accomplished thoroughly in glass vessels, and, 
of course that Davy was perfectly correct in supposing that the 
products which he described as barium and strontium, were alloys 
with mercury. Iam also under the impression that the metals 
above mentioned decompose naphtha, when heated with its va- 
por, and enter into combination with its constituents. Had the 
barium which Davy obtained, been free from mercury, it would 
hot have been fusible below a red heat, as alledged by him. 
Agreeably to my experience, that metal requires no less than a 
good red heat for its fusion. 
In a subsequent paragraph he en : “'The metal from lime I 
have never been able to examine exposed to air or under naphtha. 
the case in which I was enabled to distil the mercury from it 
to the greatest extent, the tube unfortunately broke while warm, 
and at the same moment when the air entered the metal, which 
“See Transactions of the Royal Society, Part IT. er at Journal, vol. 
xxi, for 1808 ; or, Tilloch’s Philosophical Magazine, vol. xxx 
