100 
SIE B. C. BEODIE ON THE CALCULUS OF CHEMICAL OPEEATIONS. 
In this case, again, the two events may be referred to a common cause, namely the 
substitution of £ for x- But in each case an alternative is presented to us, namely, in 
the former of the two events the transference of (6% 2 x), regarded as the symbol of a 
simple weight, and one of the prime factors of the equation, and in the latter event the 
transference of (6£ 3 ) similarly regarded. 
The event 
aQg 2 X 2 + 2a| = a0g 4 + 2a% 
is thus resolved into the constituents 
+ a %— + a x> 
aQg 3 x + a£=a0£ 4 +«*, 
both of which events may be considered to occur by the substitution of £ for 
The synthesis of this phenomenon here suggested to us has actually been realized — 
the unit of matter, olO^x, which is thus brought under our notice being the unit 
of the substance termed hydrochlorosulphurous acid, which is formed, together 
with other products, by the action of pentachloride of phosphorus on sulphuric acid, 
and is to be recognized as identical with the substance the unit of which appears in 
these equations by the property which it possesses of being resolved, together with a 
unit of water, into a unit of hydrochloric acid and a unit of sulphuric acid. 
(3) A unit of bromide of ethylene and two units of water are resoluble into two units 
of hydrobromic acid and a unit of glycol, thus 
a 3 ;* 2 /3 2 -f- 2a£ = 2a[6-\-a 3 K 2 ^ 2 . 
This equation may be thus expressed 
a(a 2 >c 2 (2-j-a 2 x 2 ^ — 2)(j3 - — £) = 0, * 
whence 
a(aV/3 -l)fl3-§) ■ + 1)(0 - 0 = 0, 
the constituents of the event being 
a(aV/3 — 1)(0 ' — 0 = 0, 
a(a 2 x 2 £ — 1)(/3 — £) = 0 . 
In these events a is constant ; the two events may be referred to a common cause, 
namely the substitution of £ for 0. The results are 
aV0 2 +a£= aj 3 + a V0£, 
aV0|+a|=«0+ a V| 2 . 
These events have been realized, the unit a 3 « 2 0|, intermediate in composition 
between glycol and bromide of ethylene, being the monobromohydrin of glycol. 
(4) A unit of diacetic glycol and two units of water are identical with two units of 
acetic acid and a unit of glycol, thus 
a 5 « 6 | 4 +2a^=2aV| 2 + a V| 2 . 
