THE RUFFED GROUSE. 155 



keeps it up until he becomes weary. This booming, 

 which is not unlike the roll of a kettle-drum, is very de- 

 ceiving, for it sometimes seems afar off, and at other 

 times quite near. This peculiarity has led some persons 

 to imagine that he possessed ventriloquial power, but 

 this is evidently a mistake, as he does not use his voice 

 during the exercise. Many sportsmen think the drum- 

 ming IS produced hj striking the wings against the log, 

 which is often hollow, and a few naturalists suppose that 

 it is caused by the violent contact of the wings with each 

 other, or with the sides, but neither of these tlieories 

 seems satisfactory, as the same sound is produced on a 

 stone or amid heavy shrubbery. The wings being par- 

 tially concave on the inner side when they are in motion, 

 it is plausible to suppose that their extremely rapid vi- 

 bration through the atmosphere, and the consequent 

 compression, expansion, and escape of the air under 

 them, would cause the drumming or booming which is 

 the cause of so much speculation among sj^ortsmen and 

 naturalists. It certainly does not seem plausible to sup- 

 pose that such a sound could be produced by beating the 

 pinions together, against the sides, or against a log, for 

 it cannot be heard any distance away until the wings 

 commence vibrating very rapidly, and it increases in 

 volume and intensity in proportion to the velocity of 

 their movement. The drumming commences between 

 February and April, according to the mildness of the 

 climate in the country where the birds have their habi- 

 tat, and is continued until all the fertile birds have 

 paired. Barren hens often drum during the summer, 

 and the young males in autumn, as soon as they separate 

 from the mother. 



The booming is heard more frequently in the morning 

 and evening than at any other time, during the calling 

 season, but it is persistent in cloudy days, and is often 

 continued all night. Some farmers and hunters say that 



