1817.) | Scientific Intelligence. 333 
his hand by a skilful mineralogist, and carefully selected for the 
purpose, otherwise little confidence can be put in the result, because 
the mineral examined may be either wrong named or impure. 
Hence it is important that every analysis should be preceded by a 
mineralogical description of the specimen subjected to analysis. 
Were it not that it would have an invidious appearance, I could 
easily exhibit specimens of very faulty analyses by first-rate chemists 
from inattention to the purity of their specimens. 
XI. On Bees’ Combs. 
(To Dr. Thomson.) 
DEAR SIR, 
When writing to you a short time since on bees’ combs, &c. I 
forgot to mention the manner in which I succeeded in parting the 
combs into the separate cell-like appearance. If a piece of virgin 
comb be put into water just below boiling, it will be seen gradually 
to melt down and spread itself on the surface of the water, without 
leaving any insoluble residue; but if a piece of old comb that ap- 
pears black, and has had brood in it, be put into water, the cells 
will gradually crack, and may then be easily separated into distinct 
pieces ; the theory of which is this, not that the cells were, or even 
are, separate; but, as I said before, after the young brood has Jeft 
the cell, the skin with which it was enveloped, and which lines the 
entire inside, instead of being taken out by the old bees, is stuck 
up to the sides. ‘Therefore, when the comb is put into hot water, 
the wax of which the cells were first composed is melted, and the 
skinny linings are separated into distinct pieces, which to a casual 
observer would appear as though the cells were absolutely made 
distinct, but which is not the case, as we see by the virgin comb 
dissolving without any residue or skin-like substance. 
I remain, Sir, yours respectfully, 
Waddon, Nov. 19, 1816. R. W. Barcuarp. 
XII. Introduction of Vaccine Lymph into America. 
Render to Cesar the things that are Casar’s, 
(To Dr. Thomson.) 
SIR, 
With much surprise I have seen it stated in Mr. Pettigrew’s 
Memoirs of the Life and Writings of the late Dr. Lettsom that 
*€ the vaccine lymph was first sent by him across the Atlantic, and 
consigned to the fostering care of Dr. Waterhouse, Professor of 
the Theory and Practice of Medicine in the University of Cam- 
bridge, Massachusetts; and that from him it was spread through 
the United States.” But this is not true. Vaccine lymph had 
been previously seut by Dr. George Pearson to Dr. John Chichester, 
now a resident physician at Bath, but at that time in very extensive 
practice at Charleston, in South Carolina. An opportunity soon 
offered for the employment of it, of which Dr. C. availed himself ; 
and the particulars may be seen by a reference to Mr, Tilloch’s 
