‘on Photogenic or Hydrocarbon-Oils from Coal. 115 
n distilling coal from a pit near Wigan in oe this observer ob- 
; tained, first phlegm Somat - oil, — finall 
o doubt an earlier record of sim sexperts might be fond 4 in the 
writings of the sche niece; whoa as is well known, subjected almost every sub- 
stance ~ processes of distillatio 
a g the last conenry attention was again several times called to the 
‘t mente seem, however, that erent very definite was published before the 
ar 18 Unverporsent had, indeed, in the ain year, Ss atten- 
Son to oils distilled from petroleum, on even appears to have obtained paraf: 
0 which how € gave me.t The attention of the vacivstifie 
memorable memoit 
ic 
at great pains to prove e that sie. rade. obtained by slowly distilling coal, 
y heat; and that the coal-tar of gas-works is not crude-oil, but an impure 
weed of the pr jeduce of distillation ith one resulting from their decom- 
positio 
* In addition to the authorities cited by Dr. A. (p. 8), we would mention the fol- 
lowing from A 1 A An _ Bape erimental History of the Materia Medica, or of the Natural 
t ct ode 
and Arti fics use of in Medicine ; by W1ittam n Lewis, MB, ERS. : 
3rd Edit! 8vo, Dublin, mpootxrx, vol. ii, p. 143, Article Petroleum ; also, (accord- 
7 to - erg Druggists’ Cthealay, iv, 86,) in the London edition of we 4to, 
436: 
“ Some mineral oils, a ag among ourselves, are used by the common people, 
: and often with benefit, The empirical medicine, called British oil, is of the same 
j nature with the petr ee the genuine sort being extracted by distillation — a 
harc bitumen, or akind of stone coal, found in at and other parts 0 f Eng- 
Schocigger-S ae Journal fir Bhemié Fal Pingu 1829, Iviii, 24 
’ t For allusions to other earlier German researches bearing upon ‘the seat see 
Reichenbach’s Memoirs, which will be cited directly. Compare also Gmelin’s 
oe Handbook of Chemistry (Cavendish ee Eudit.), xii, 439. 
i § Journal fiir Chemie und Phy (or Ja arbuch der Chemie u. Physik, Band, 
" XxIX) von ate a Seidel, 1830, 
cap beth teat es Jahrbuch der Onaate’ u. tects tema that “in 1880-'81 
r. Antis Pr a , 
Reichenbach ell diamines ae alin.” bee (p. aa i be amiss to state that one pagent 
Garpen in 1820 
also loc, cit. B. Ixviii, [B. viii, of the * Newes-Jalrbu 
must here My expiined that that Reichenbach has cere great aaa at oo 
ing por 
e Ww n 
“ Steinkohlentheer” hie pity sienna 
: f ," Yiterall —coal-tar. Now the term coat-tar, 
in gas-works rod fea la rt’ ae the United States, means the tar of gas-works, and it 
emembi 
Means nothing ust ae mbered, were, until quite recently, 
Or tiene ph e. “Gus: -works, it mus d wete doubtless rare enou a os 4 
Sequently, it is rt Enalish idea of “ coal-tar” shoulc not have 
become °. . vieckon county, sichanbach , for os tae. distinctly and tu 
ie ee merit, “ ; heer” is a very different substance from the 
orks. that ae Steinko ee oil. If, Si cadte: there may be any per- 
= — os s of clatranlalit certain words used by Reichenbach. we 
Would at once refe ry vinal aiarobite of this author. Submitting it 
to the judgmen of feck an one “ ae, whether we have misinterpreted his lan- 
