402 Intelligetice and Miscellaneom Articles. 



the slight announcement in the public papers, that it had been seen 

 at Slough, probably with one of Sir John Herschel's powerful tele- 

 .scopes. We have not heard, however, of any other person having been 

 able to detect it. By an extract from a recent New York paper, it 

 would appear that it has been seen in America ; but we much doubt 

 whether there exists in the whole of the United States a telescope 

 powerful enough to detect the faint light which this comet is known 



to exhibit. 



ON PARAFFIN AND EUPION. 

 Dr. Reichenbach has discovered two substances by the dry distil- 

 lation of organic bodies, to which he has given the above names. The 

 first from parum affinis, on account of its remarkable indifference or 

 want of affinity ; and the second from ttiwv or ■jriov fat, and ev. These 

 substances appear to be both contained in the tar of animal and 

 vegetable substances. Beech-wood tar yields the most paraffin, and 

 with the greatest facility; while the oil of Dippel gives mosteupion. 

 If the tar obtained by the carbonization of beech-wood be sulyect- 

 ed to distillation, the receiver, provided it has not been changed nor 

 removed, contains three different liquids : at the lop, light oil of tar, 

 in the middle a waterv acid liquor, and at the bottom heavy oil of 

 tar. This last is to be subjected to repeated distillation ; and when 

 the product l)ecomes rather thicker, and contains small shining par- 

 ticles, the receiver is to be changed, and the heat is to be increased 

 as much as the glass will allow of, and until the residue becomes 

 black and thick. The receiver then contains a yellow thick vapour, 

 and an oily liquor, in which brilliant particles of paraffin are observ- 

 able by transmitted light. If the liquor has not acquired the proper 

 state, it is to be obtained by repeated distillations, and the paraffin 

 may be separated in two different modes. 



The first consists in mixing and shaking the distilled liquor with 

 alcohol of specific gravity 0-8,i7. After standing a little time, there 

 deposits from the turbid mixture, a viscid liquid mass, which is to be 

 repeatedly washed with alcohol of the same strength, until it is con- 

 verted into small colourless plates. These are then to be dissolved 

 iti hot absolute alcohol, and as the solution cools, paraffin separates 

 in small white needles, and in small plates : in order to purify thein 

 perfectly, they may be redissolved in hot absolute alcohol, from which 

 they separate on cooling. 



The following is a belter method : Distil the heavy oil of tar re- 

 peatedly, and mix it gradually with one tenth of its weight of con- 

 centrated sulphuric acid, adding this quantity repeatedly until the 

 mixture has become entirely black and fluid ; this action is attended 

 with heat and the evolution of sulphurous acid ; the oil requires from 

 a quarter to a half its weight of acid. If the heat does not rise to 

 '212- Fahr. it must be raised to that degree artificially. The mixture 

 is then to remain at least twelve hours exposed to a heat of not less 

 than 124° Fahr., in order that the paraffin may not congeal; it 

 then is found as a colourless liquid on the surface. Decant this liquid, 

 which is a compound of paraffin and a peculiar oil ; or when all is 

 cold, let it be taken off in a cake, break it, wash it with water, and 



