CARBOLIC OR PHENIC ACID AND ITS PROPERTIES. 
481 
smell which it still possessed was a serious obstacle to its application. I soon succeeded 
in overcoming this difficulty, and towards the end of the year J864 our firm was in a 
position to deliver in considerable quantities carbolic acid deprived of sulphurous com¬ 
pounds, and therefore fit for all medicinal uses. But I am glad to say that the series of 
improvements in the manufacture of pure carbolic acid did not stop there, for towards 
the end of last year I discovered a process which now enables me to show you a product 
completely deprived of all disagreeable odour and tarry flavour, and, in fact, as pure, 
though extracted from tar, as if it had been produced artificially by the help of the re¬ 
actions recently discovered by Messrs. Wurtz and Kekule, based upon the direct trans¬ 
formation of benzine into carbolic acid, or by the well-known changes by which it may 
be obtained from salicylic acid or nitro-benzoic. This carbolic acid is distinguished from 
Laurent’s in being soluble in 20 parts of water, whereas the latter requires 33. It is 
fusible at 41, instead of 34, and boils at 182 degrees, iustead of 186, but it gives, like 
Laurent’s, the blue colour described by M. Berthelot when mixed with ammonia, and 
to the solution is added a small quantity of a hypochlorite ; the same effect is also pro¬ 
duced when you expose to the vapours of hydrochloric acid a chip of deal soaked in this 
pure carbolic acid. 
It was supposed that, as Laurent’s acid had a constant boiling- and crystallization- 
point, it was a pure and definite substance. Now, the production of our new acid shows 
it is nothing of the kind, the product of Laurent being only a mixture of our pure 
carbolic acid and a liquid homologue ; for when to the acid of Laurent is added a cer¬ 
tain proportion of water, and the mixture is exposed to a temperature of four degrees 
Centigrade, it deposits a crystalline substance in large octahedrons; this substance is a 
hydrate of carbolic or phenic alcohol, that is to say, carbolic acid combined with an 
equivalent of water of crystallization. This fact is important in a chemico-theoretical 
point of view, for it exhibits the only example known of an alcohol which, combining 
with water, forms a crystallized and solid hydrate. By removing from this hydrate the 
equivalent of water which it contains, carbolic acid is obtained in its purest state. 
W e will now rapidly glance at the applications which have been made of this product 
for sanitary purposes, in medicine, agriculture, and manufactures. 
The disinfectant, or rather antiseptic properties of carbolic acid, are very remarkable. 
The beautiful researches and discoveries of M. Pasteur have shown that all fermentation 
and putrefaction is due to the presence of microscopical vegetables or animals, which, 
during their vitality, decompose or change the organic substances, so as to produce the 
effects which we witness, and carbolic acid exercises a most powerful destructive action 
upon these microscopic and primitive sources of life. Carbolic acid, therefore, is an 
antiseptic and disinfectant much more active and much more rational than those gene¬ 
rally in use. 
And allow me further to add that disinfectants, such as chlorine, permanganate of 
potash, or Condy’s fluid, operate by oxidizing not only the gaseous products given off by 
putrefaction, but all organic matters with which they may come in contact; whilst car¬ 
bolic acid, on the contrary, merely destroys the causes of putrefaction, without acting 
on the organic substances. The great difference which, therefore, distinguishes them, 
is, that the former deals with the effects, the latter with the causes. Again, these small 
microscopic beings, these ferments, are always in small quantities as compared to the sub¬ 
stances on w r hich they act; consequently a very small quantity of carbolic acid is 
necessary to prevent the decomposition of substances ; .therefore, its employment is 
both efficacious and economical. Moreover, carbolic acid is volatile; it meets with 
and destroys, as Dr. Jules Lemaire says, the germs or sporules which float in the 
atmosphere, and vitiate it, and this cannot be the case with Condy’s fluid, chloride 
of zinc or iron, which act only by contact, and are mere deodorizers. This is why 
carbolic acid was used with such marked success, and therefore so largely, in Eng¬ 
land, Belgium, and Holland during the prevalence of cholera and of the cattle 
plague. The antiseptic properties of carbolic acid are so powerful that even 
Woo prevent the decomposition, fermentation, or putrefaction for months of urine, 
blood, glue solution, flour, paste, faeces, etc., etc.; in fact, its vapour alone is sufficient 
to preserve meat in confined spaces for weeks ; a little vapour of this useful substance 
will preserve meat for several days in the ordinary atmosphere, and prevent it being fly¬ 
blown ; lastly, has been found sufficient to keep sewage sweet; and I am proud 
to say that the British Government have decided to use exclusively our carbolic acid (as 
YOL. IX. 2 I 
