(Gia) 
XXVIII.—On some Derivatives from the Olefines. By FrepErick GUTHRIE, 
F.R.S.E., Professor of Chemistry in the Royal College of the Mauritius. 
(Read 18th March 1861.) 
Some years ago I commenced an examination of the behaviour of the so-called 
olefines towards certain compound halogens. I was induced to this by the con- 
viction that the bodies resulting from the union of a group of unequally chemico- 
negative elements with an olefine, would place an instrument of great power 
into the hands of systematic chemists, especially of synthesists. My expectations 
have been more than realized. The few olefines which I have examined in their 
relation to compound chemico-negative groups have given rise to a series of new 
bodies remarkable alike for their great number and for the elegance and import- 
ance of the reactions attending their formation and recompositions. , 
It will probably be found that the Ketons and other oxygeniferous bodies may 
enjoy some of the properties of the olefines proper: but we must be content to 
define an olefine provisionally as a hydrocarbon capable of uniting directly with 
halogens. According to this definition, we find olefines falling naturally into two 
groups. Of the one group, Naphthaline is the sole representative. This olefine 
unites with two or four equivalents of halogen, to form, expressed generally, 
CoH XG Cs KKK, 
and the numerous class of bodies idiotypic with these, of which. the following are 
examples : 
Ope 00 Ae UNC 2.8.6 
The other group of olefines has the general formula 
Con Ho. 
For the chemical saturation of the members of this group, two equivalents of 
halogen are necessary and sufficient : 
Con Hon XX. 
Bertueior has shown that an olefine of the latter form may indeed unite 
with a hydrohalogen and that the result is a body identical with the halide of 
the corresponding radicle. 
Con H.,+ HxX=C,,H Gree 
C, H,+H Br=C, H, Br 
VOL. XXII. PART III. 77 
