112 Fossil Vegetables. 
lapidary will find it advantageous, to fix the glass in a groove: made 
in a small piece of wood. The groove should be a little less deep 
than the thickness of the glass, and the wood itself should project 
half an inch beyond each side. 
A lapidary will thus find no difficulty. i in reducing, and polishing 
any piece of petrified wood to the ore of thinness, sufficient to 
render its structure visible. 
With the hope of exciting the gable attention in this country ts to 
this very interesting subject, we subjoin a letter from Mr. Witham 
to the editor, with his reply. . 
TO PROFESSOR SILLIMAN. 
Sir—In perusing your Journal, I perceive you are anxious for 
the promotion of all branches of science in the various. departments, 
and as it appears to me, that little attention has hitherto been paid 
in America to the peculiarities of fossil vegetation; I have therefore 
taken the liberty of sending one or two memoirs, and a short work 
upon that department of the botanical field. Owing to the great opa- 
city and consequent difficulty of obtaining insight into the internal 
structure, of fossil vegetables, they have been, until lately, much neg- 
lected. You will now perceive that by a new mode of cutting, slicing 
and grinding, you will be able to obtain the internal structure of any 
plant that retains its structure. Should you, by your persuasion, be 
able to set labourers to work in your extensive coal fields, it may 
lead to comparisons, both curious and highly instructive, and any 
communications received from you, will be most gratefully received, 
by, Sir, Your obt. — H. Wirnam. 
Lartington, Greta Bridge, Yorkshire, } ene 
M4 Grea — Street, Edinburgh, Apri 5. 
REPLY. ‘ 
Yale College, July 11, 1833. 
Sir—A few days ago, I had the pleasure of receiving your kind 
letter of April 5th, with several copies of your two memoirs, for which 
I beg you to accept my best thanks. ‘They have interested me very 
rauch, and I shall give in the Am. Jour. a short notice of your discov- 
eries. In 1830, I republished the first observations which you had 
then made; and still earlier, those of M. Alex. Brongniart, in the 
coal of St. Etienne, in France. You have opened a very inter- 
esting field of inquiry, and I doubt not that the progress of explo- 
ration, in this country, will add to the mass of similar facts. I have 
