Utility and mi i of Birds . 
vants than the HomMInG PIGEONs of his army 
and navy. 
It is of interest to note that PARROTS were 
employed, early in the war, at the Eiffel 
Tower to announce the approach of hostile 
aircraft. It was found at first that the birds 
gave warning fully twenty minutes before 
an aeroplane or airship could be identified 
by the eye or heard by the human ear. The 
birds, however, which could never be trained 
to discriminate between a French and a 
German aeroplane, appear to have grown 
indifferent or bored, so that they ceased to 
be trustworthy (Daily Mail, 1.11.18). 
It is well known that CANARIES, being 
about fifteen times more sensitive than a man 
to poisonous gases, are used in mines and 
in mining disasters to test atmospheric con- 
ditions and save miners or explorers from 
gas-poisoning. The Government Mines Com- 
mittee recommended that two or three birds 
should be kept at rescue stations for the 
testing for carbon-monoxide. Our soldiers 
on the Western Front are said on one occa- 
sion to have been warned, by the behaviour 
22 
