562 Chronicles of Science. [Oct., 
being both liquid and seriform; they can be at once added to 
discharges, and constantly diffused in the air. 
“ All these four substances—chlorine, ozone, sulphurous acid, 
and the tar acids—have been practically tested, either in England 
or on the Continent, and there is considerable evidence that they 
all actually do destroy the cattle plague poison. Their precise 
mode of action is still uncertain. Chlorine and ozone act, no doubt, 
as powerful oxidisers, converting animal poisons into simple and 
innocuous substances. Sulphurous acid probably destroys the virus 
by its strong antiseptic powers. The tar acids, according to the 
experiments of Mr. Crookes, neither interrupt nor accelerate oxida- 
tion, but they act most powerfully in arresting all kinds of fermen- 
tative and putrefactive changes, and annihilate with the greatest 
certainty all the lower forms of life. 
“ After a full consideration of the relative merits of the four 
disinfectants, and after some practical trials, Mr. Crookes arrived 
at the conclusion that the most powerful, and at the same time 
most simple, process of disinfection would be to use the tar acids as 
constant liquid and aeriform disinfectants, and sulphur im the form 
of sulphurous acid as an additional and occasional agency. 
“For the reason stated in Mr. Crookes’s report, it appears that 
chloride of lime is inferior to the combined use of carbolic and 
sulphurous acids. But there is no doubt of the efficacy of this 
agent, and in certain circumstances, as for the washing of railway 
trucks, it may be employed in addition to boilmg water or steam. 
“ It is very desirable that the use of carbolic acid should become 
general throughout the country in uninfected as well as in infected 
districts. There is little doubt that even were there no danger 
from the cattle plague, the great purifying effect of this substance 
on the air of cattle sheds would contribute greatly to the health of 
the animals.” 
We presume that a very long experience of the use of carbolic 
acid is necessary before its permanent efficiency can be determined ; 
but in the mean time its cheapness, easy applicability, and power of 
at once arresting all kinds of putrefactive change, doubtless justify 
all that the Commissioners say in its favour. 
In connection with this subject we have to add that all attempts, 
arising out of this national calamity, to establish a National 
Insurance Society and Fund have failed. Dr. Farr, F.R.S., did, 
indeed, read a paper last June before a meeting of the English 
Agricultural Society, advocating a plan which he had drawn up, by 
which the whole live stock of the country might have been insured 
by Government upon the voluntary principle; but no action 
followed upon it. To establish such a society, the first thing neces- 
sary was that noblemen and gentlemen interested in agriculture 
should subscribe to a guarantee fund, on the plan adopted at the 
