'20 Mr. J. Blackwall's Observatio?is on the Notes of Birds, 



young green grosbeaks, — a cock and two hens ; which, as they 

 did not see till the fourth day after they were taken from the 

 nest, must then have been only two days old *. 



These birds were reared by hand, in a house situated in the 

 town of Manchester, where they had no opportunity of hear- 

 ing the notes of any bird, except, perhaps, the occasional 

 chirping of sparrows : nevertheless, they had all their appro- 

 priate calls, and the cock bird had the song peculiar to its 

 species. 



It was hoped, at the time, that this experiment would be 

 considered sufficiently decisive; but recollecting that some 

 persons, for the sake of showing their ingenuity in raising ob- 

 jections, might say that these birds remembered the notes of 

 their parents, which they imitated as soon as they had acquired 

 the power ; and being willing to remove every circumstance 

 on which the most fastidious inquirer could fix a doubt, I 

 placed the eggs of a redbreast in the nest of a chaffinch, and 

 removed the eggs of the chaffinch to that of the redbreast ; 

 conceiving that if I was fortunate in rearing the young, I 

 should by this exchange insure an unexceptionable experiment, 

 the result of which must be deemed perfectly conclusive by all 

 parties. In process of time these eggs were hatched, and I 

 had the satisfaction to find that the young birds had their ap- 

 propriate chirps f . 



When ten days old they were taken from their nests, and 

 were brought up by hand, immediately under my own inspec- 

 tion, especial care being taken to remove them to a distance 

 from whatever was likely to influence their notes. At this 

 period, an unfortunate circumstance, which it is needless to 

 relate, destroyed all these birds, except two, — a fine cock red- 

 breast, and a hen chaffinch ; which, at the expiration of twenty- 

 one days from the time they were hatched, commenced the 

 calls peculiar to their species. This was an important point 

 gained, as it evidently proved that the calls of birds, at least, 

 are innate ; and that, at this early age, ten days are not suffi- 

 cient to enable nestlings to acquire even the calls of those un- 

 der which they are bred ; thus clearly establishing the validity 

 of the first experiment made with the young green grosbeaks. 

 Shortly after, the redbreast began to record :j:, but in so low 

 a tone, that it was scarcely possible to trace the rudiments of 



* From numerous observations that I have made, it appears that young 

 birds usually begin to see about the sixth day after they are hatched. 



f Mr. Barrington defines the chirp to be the first sound a young bird 

 utters as a cry for food. It consists of a single note, repeated at short in- 

 tervals, and is common to nestlings of both sexes. 



% The first endeavours of a young bird to sing are termcil recording. 



its 



