Seybert^s Analysis of Pyroxene. 145 



carries over the vapor of the tar, and mixes it with that of 

 the water J when the proportions are right, it is then 

 curious to observe the very white, silver-Hke appearance of 

 the flame. When the snapping of the tar would be incon- 

 venient, it may be prevented by boiling it a few minutes be- 

 fore it is used, to get rid of the coarser particles of water. 

 But when it is desired to give a steady, durable light of any 

 size with tar, the best mode I have yet tried is to raise the tar 

 by machinery to the upper part of the tar vessel, passing it off 

 through a small tube into a small cup, say to hold half a gill. 

 Another small tube, from near the bottom of the tar vessel, 

 passes upward through this little cup, about two thirds the 

 way to the top. The machinery for raising the tar may be 

 kept in motion by connecting it with any moving power. 

 The tar, when raised, flows out into the small cup, is there 

 iflflamed, and then continues to burn, without any further 

 attention, so long as the supply is kept up. It is furnished 

 faster than it is consumed, but the overplus flows out before 

 the small cup is full, down the small tube into the tar ves- 

 sel at bottom, where, by its high temperature, it preserves 

 the body of the tar at a temperature that makes it flow free- 

 ly if ever so cold. As the tar in this little cup is all that is, 

 or can be inflamed at a time, it renders it perfectly safe, 

 and the time of burning in a sense unlimited. 



Yours very respectfully 



SAMUEL MORE If. 



PllOP. SlLLIMAN. 



Art. XIX. — Analysis of the Pyroxene, found at the Frank- 

 . I'm Iron Works, near Sparta, Sussex Co. Kew-Jersey, by 

 Henry Seybert. 



An account of this mineral, by Messrs. Wm. H. Keating, 

 and Lardner Vanuxem, was published, in the Journal of the 

 Academy of Natural Sciences in this city.* After an at- 

 tentive examination, they decided, that it was a new species, 

 and called it Jeffersonite. Mi. Keating analysed it, and this 

 they observe " fully confirmed the conclusions drawn from 

 its mineralogical characters." His analysis gave the fol- 



* Journal of the Academy, Vol. 2, p. 194. 



Vol. VII.— No. 1. 19 



