350 INSECTIVOIL-E. 



quantity of the voice to those of an echo returned from the 

 distance of the object from which they wish the sound to 

 appear to come: they do that by measuring the distance 

 with the eye, just as a speaker does when addressing some 

 particular person in a crowd; in which case the tone and 

 quantity of the voice alter, and that person hears better than 

 even those between him and the speaker. But the distance 

 can also be measured mentally, as sailors who have come to 

 the buoys in a fog, can "halloo a harbour" to the pilot. The 

 voice of the birds is instinctive ; but it is also made up partly 

 of echo-notes, in all cases where it is ventriloque, or varies in 

 apparent place, while the bird remains in the same ; and it is 

 a curious property of those echo-notes, that they cannot be 

 well returned in a real echo. 



WAEBLERS (CllTTUCCL). 



Though all the little birds are interesting, as associated 

 with nature, with innocence, and with beauty, there is a 

 peculiar interest about the warblers. The birds which remain 

 constantly with us, and come round our dwellings in the 

 inclement season, give that season sprightliness by their 

 appearance, and hail with their songs any warm day that 

 breaks out. But the constancy of their appearance takes off 

 some of the interest which, if they were as novel as they are 

 beautiful, they would more certainly command ; and as their 

 songs, breaking out as they do in the intervals of the storms, 

 are no certain signs that the life of the year has begun, we 

 do not listen to them with the same attention and satisfac- 

 tion as to the migrant warblers. 



The song, or the other demonstration of spring, given by 

 the resident bird, tells us merely of the state of the season in 

 our own country, of which we have other means of judging ; 

 but the summer or rather the spring migrant brings us 



