ANALYSIS OF CONTINENTAL JOURNALS. 
335 
did not take the infection, because they were still under the 
influence of a previous vaccination, which still gave them 
immunity. Can there be a greater proof in favour of the 
efficacy of vaccination ? 
The efficacy of the animal vaccine is no longer doubtful; 
its purity in respect to syphilis is self-evident; and its 
abundance is such as to suffice for all eventualities and wants, 
and it is also free from all morbific matter likely to cause 
local disease, which has been fully established by experience. 
In fact, there can be nothing against it, unless it is dictated 
by envy and prejudice. 
Marchal (de Calvi). 
We have given this article in extenso , on account of its 
interest in reference to the absurd opposition to vaccination 
in this country of late. 
The following Circular has heen addressed to the Governors of the 
Provinces by the Minister of the Interior of Belgium, 
Your Excellency, — No rule has been laid down for the 
guidance of the local authorities in reference to the period 
which should elapse before the reintroduction of cattle into 
the sheds where contagious pleuro-pneumonia has been ascer- 
tained to exist, or the free circulation of animals or of the 
bovine species who have been in contact with animals affected 
with that malady. 
The number of cases of relapse which have occurred in 
certain localities, the virulent form which this contagious 
malady tends to assume, demands the most severe measures 
to be taken to prevent considerable losses being sustained by 
agriculturists. 
Experience seems to prove that the period of incubation of 
pleuro-pneumonia epizootica varies very considerably, and that 
the term of incubation being rather long, it therefore w r ould 
not be prudent to permit the free circulation of animals 
which, by their cohabitation with diseased cows, might be 
considered infected w T ith the malady. 
It is therefore important that the local authority should 
order the sequestration of animals during at least forty-five 
days after the last case of the malady has occurred. 
In reference to the introduction of fresh cattle into the 
