306 Scientific Intelligence. 
3. Supposed identity of Copal and Amber. 
A correspondent, whose paper is withheld from publication 
till some additional experiments can be made, conceives that 
copal and amber are originally the same substance, and the pro- 
duct of the same tree. 
4. Tue Necronire.—(.1 supposed new Mineral.) 
Extract of a letter from Dr. H. H. Hayden of Baltimore, to the 
Editor, dated January 5, 1819. E 
“it (the necronite) occurs in a primitive marble, or lime- 
stone which is obtained 21 miles from Baltimore, and asm 1 
_ distance from the York and Lancaster road. It was ar no- 
ticed by myself at Washington’s monument, in which this marble 
is principally employed. #3 
“It occurs, for the most part, in isolated masses in the 
blocks or slabs, both in an amorphous and crystallized state. 
It ig most commonly associated with a beautiful brown mica, 
of the color of titanium; small but regular crystals of sul- 
phuret of iron, tremolite, and small prismatic crystals of tita- 
nium, which are rare, The form of the crystals is a rhom- 
boid, approximating very much to that of the felspar, and 
which has inclined some to consider it as such. Also, the hex- 
aedral prism resembling that of the beryl. This form is rare; 
and has not, as yet, I believe, been found complete. Its color 
is a bluish white, and clear white. Its structure much resem 
bles felspar, being lamellar; sometimes opaque, semi-trans 
parent, and transparent at least in moderately thin pieces. It 
scratches glass, carbonate of lime, and even felspar, in a slight 
degree. In all our efforts, it has been found infusible, pet 5° 
or with borate of soda, and even from all the force’ f heat 
that could be excited in a smith’s furnace, it came oul 0 
changed in any degree. The acids seem to have no sensible 
efiect upon it, either cold or hot. This is all that I cam say 
of it at present, except that it possesses a most horrid smell." 
“On account of its peculiar cadaverous odour Dr. Hayden proposes to call this 
mineral (should it prove to be anew one) Necronite, from the Greek Nexp% 
