GUPPY — XOTE OX PETROLEUM A YD 1ST APHTHA. 
139 
After stating that Petroleum is native naphtha, a term 
originally applied to the inflammable liquid compound of 
hydrocarbons issuing from the soil in Persia, the author ex- 
plained that the rock-oils found in other parts of the world 
do not differ materially, being compounds of three hydro- 
carbons. The hydrocarbon series includes a vast variety of 
organic and mineral products, as coal, asphalt, peat, oils, 
resins, &c., &c. Certain of these are dangerous on account 
of their vapor when mixed with atmospheric air becoming 
explosive on the application of flame. Well refined oil is 
not dangerous, but any oil the vapor of which is inflamma- 
ble at a lower temperature than 120° can hardly be consi- 
dered quite safe. 
The author pointed out the mistaken use of the terms 
i 1 Pitch” and “ Pitch Oil” as applied to the asphalt of 
Trinidad and the Petroleum Oil, Kerosine Oil or other 
products of asphalt and petroleum. 
Tuesday 11 th June, 1867. 
The Hon. Henry Stuart Mitchell, M.D., Ph.D., Presi- 
dent, in the Chair. 
John Niven, Esq., Port- of- Spain, was elected a Member. 
The following Yisitor was introduced : — Dr. William 
Henry Stone, P.R.C.P., by Mr. Lechmere Gfuppy. 
The following communication was read : 
Additional Note on the Use of Sulphites and Bisulphites , 
whether Medicinally or otherwise . 
By the Hon. Henry Mitchell, M.D., Ph.D. 
I had hoped, Gentlemen, to have laid before you this 
evening some special remarks on the medicinal use of a few 
of the compounds of Sulphurous Acid. In this, however, 
I am disappointed, as the paper which contained them has 
