In Blythe's process the timber is dried, and crude carbolic acid injected.
In all cases of carbolic acid poisoning the nervous influence is seen.
A piece of cotton wool soaked in strong carbolic acid will relieve the pain of dental caries, but is useless in other forms of toothache.
In early inquiries a great point was made of the prevention of putrefaction, and work was done in the way of finding how much of an agent must be added to a given solution, in order that the bacteria accidentally present might not develop. But for various reasons this was an inexact method, and to-day an antiseptic is judged by its effects on pure cultures of definite pathogenic microbes, and on their vegetative and spore forms. Their standardization has been effected in many instances, and a water solution of carbolic acid of a certain fixed 'strength is now taken as the standard with which other antiseptics are compared.
Amongst the best of these are carbolic acid in doses of one or two grains, creosote in one or two drops, and sulpho-carbolate of soda in doses of ten grains.
The symptoms of nerve-poisoning are due to the carbolic acid (or its salts) which circulate in the blood after all the sulphates in the blood have been used up in the formation of sulpho-carbolates (hence, during administration of carbolic acid, the urine should frequently be tested for the presence of free sulphates; as long as these occur in the urine, they are present in the blood and there is no danger).
But carbolic acid and caustic potash destroy it only after a day or two, consequently they are not a remedy.
It is much more powerful than carbolic acid in its inhibitory action upon unorganized ferments such as pepsin or ptyalin.
They also expressed the opinion that carbolic acid was a valuable agent in restraining tetanus growth when added to plague prophylactic, ' and they, therefore, thought that its omission was a grave mistake.
These all resemble carbolic acid more or less closely, and may be described as general protoplasm poisons.