224 Mr. A. B. Northcotc on Parathionic Acid. 



acid ; and it is not difficult to conceive this change to be due 

 generally to the tendency of complex molecules to assume a 

 simpler form, and in particular to the same striving, as it were, 

 of the atoms of hydrogen and sulphuryle to approximate more 

 closely to that of sulphuric acid, which we have already seen : 



CHn H . CH 2 .H] rH3 . 



so 2 lo 2 +jHo= soHo 2 + h [o. 



The sulphuryle in this decomposition has obtained one atom of 

 hydrogen. May it not induce such a partial separation of 

 another atom from the molecule CH 3 as shall suffice to consti- 

 tute the modified sulphomethylic acid ? That the alcohol sepa- 

 rated is of the ordinary form is shown by its boiling-point ; but. 

 whether the ordinary form or an isomer be produced, appears to 

 be dependent upon the kind of change involved. If an atom of 

 methyle interchange with an atom of hydrogen of the water, the 

 result would be the ordinary alcohol; if, on the contrary, the 

 atom of methyle decompose, and, leaving an atom of hydrogen 

 behind, should pass over as methylene to the water, then a 

 modification would be produced such as Wurtz's isomer of the 

 amyle alcohol. 



And finally comes the case to which I would draw attention 

 — the long-continued action of potash on absolute alcohol. 

 Does it not resemble that of the oil of vitriol in Regnault's 

 experiment ? Recently made solution of potash in alcohol yields, 

 so far as my observations have gone, no salt of this kind; but 

 may it not be thought that, after a considerable lapse of time, 

 with the powerful affinity of potash for water constantly present 

 to the molecule of alcohol, some portion is thrown into a state 

 of different molecular arrangement which might almost be called 

 polar ? 



C 2 H 4 . 



the integrity of the molecule of alcohol being by no means 

 broken up, but yet so changed in arrangement as to yield, when 

 brought into contact with sulphuric acid, a compound other than 

 ordinary sulphethylate. To this also the fact bears testimony 

 that it is obtained by simple saturation with but the slightest 

 rise of temperature, just as parathionic acid is produced when 

 oil of vitriol at the ordinary temperature absorbs defiant gas ; 

 whereas to produce ordinary sulphethylic acid, some length of 

 contact or application of heat is necessary. It might be objected 

 that, if this view were correct, Wurtz's isomer of amyle alcohol 



