306 Saentific 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 

 Gopal and amber are originally the same substance, and the 

 product of the same tree. 



4. The Negronite. — [A supposed new mineral.) 



Extract of a letter from Dr. H. H. Hayden of Baltimore, to the 

 Editor, dated January 5, 1819. 



" It (the necronite) occurs in a primitive marble, or lime- 

 stone, which is obtained 21 miles from Baltimore, and a small 

 distance from the York and Lancaster road. It was first no- 

 ticed by myself at Washington's monument, in which this mar- 

 ble is principally employed. 



" It occurs, for the most part, in isolated masses in the 

 blocks, or slabs, both in an amorphous and crystalhzed state. 

 It is most commonly associated with a beautiful brown mica, 

 of the colour 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 colour 

 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, carbonat of lime, and even felspar, inB. slight 

 degree. In all our efforts, it has been found infusible, per se, 

 or with borate of soda, and even from all the force of heat 

 that could be excited in a smith's furnace, it came out un- 

 changed in any degree. The acids seem to have no sensible 

 effect upon it, either cold or hot. This is all that I can 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 a new one) Necronite, from the Greek Nsxgof. 



