BIRDS TRAINED TO PERFORM 143 



arouse the soundest sleeper. Guinea-fowl are 

 often maintained on poultry farms merely for 

 the sake of the protection they afford against 

 night prowlers. 



During the World War the pheasants in Eng- 

 land developed into fairly responsible sentinels 

 against Zeppelin attacks. The birds seemed 

 particularly sensitive to far-off explosions and a 

 raid generally was heralded by a concerted crow- 

 ing of cocks. It is even asserted that the crow- 

 ing sometimes preceded the actual attack by 

 from fifteen minutes to half an hour. When 

 the voices of the pheasants were heard raised in 

 alarm, the air-men looked to their machines and 

 the gunners manned their anti-aircraft pieces.^ 



Canaries also are employed to detect danger^, 

 though in a very different manner. It has long 

 been recognized that they are about fifteen times 

 as susceptible to the effects of carbon monoxide 

 and other poisonous gases as are human beings. 

 Thus, for generations these birds have proved of 

 the utmost value in mines for detecting the first 

 traces of noxious fumes. During mine disasters 

 they are used by rescuing parties to give warn- 

 ing of renewed danger. 



Canaries were utilized in the World War as a 

 part of the equipment of the sappers in their 

 tunneling operations. They saved many lives, 

 usually at the expense of their own, through 



1 Gladstone, "Birds and the War." 



