318 
HYDRARGYRUM CUM CRETA. 
Accompanying the Hydrargyrum cum Creta, I send a 
sample of Hydrargyrum cum Magnesia, made in the same 
manner, the proportions being those laid down in the Dis- 
pensatory of Drs. Wood and Bache. 
It is my intention to prepare another portion of Hydragy- 
rum cum Creta, with a view of ascertaining whether the in- 
troduction of a few dozen small pieces of gravel would not 
materially hasten the preparation, by causing a more speedy 
breaking up of the globules ; and as no deterioration could 
possibly result, I am disposed to regard the suggestion as an 
improvement. 
By triturating in separate mortars a portion of each sam- 
ple of Hydrargyrum cum Creta sent, with a small quantity 
of distilled water, I find that while in both the globules of 
mercury reappear, they are not so numerous or large in 
that made by succussion as in the other. From this, it ap- 
pears to me, two facts necessarily result : 
1st. That no possible advantage can accrue from the ad- 
dition of any substance, other than the gain of a little time, 
which should never of itself be allowed to enter into conside- 
ration in the preparation of any medicine. 
2d. That the perfection of the preparation depends in a / 
great measure, if not altogether, upon the minuteness of 
comminution, which can be carried to an almost indefinite 
extent by bestowing a corresponding amount of time and 
labour in the succussion. 
[Accompanying the above paper, we received two sam- 
ples of Hydrargyrum cum Creta : one " received from one 
of the best importing drug houses in New York." Its colour 
has a reddish tinge, precisely like that described at page 113 
of this Journal, and like it contains a considerable amount of 
red oxide of mercury. The other specimen was made by 
Dr. Coxe, and presented all the characteristics of a good 
preparation. — Editor.] 
