As an instantaneous reward the teacher let a flood of light into the dark room, in accordance with Pierre's code. More, he proceeded to give his hungry pupils a little--only a little--food, enough, in fact, to make them ravenous for more. Then he plunged the little room in sudden darkness again by shutting out the light. Thus Jerry gradually educated the birds into connecting the idea of food and light with the sound of his little instrument's melody. After two or three repetitions of this performance, it followed that the finches, kept on short commons, no sooner heard the notes of the bird-organ always playing the one unvarying tune, than they, too, attempted to sing it, in the sheer hope of being fed, and of seeing the hated darkness disappear. Jerry being ever careful not to disappoint their expectations, the result came to pass that the particular melody was committed to memory--the tune was learned, more or less correctly; for the feathered pupils were like human scholars, in that the few, not the many, arrive at perfection. After this reward for his enormous patience, Jerry Blunt's next move was to board out his pupils in the village with trustworthy boys who were selected for the posts of pupil-teachers. One boy was appointed to each bird, in order to carry out the business of teaching _the_ tune by whistling it incessantly until the air was firmly fixed in those tiny memories, which, if they had not been exactly 'wax to receive,' proved 'marble to retain.' As the finches grew perfect in their one life-lesson, the Scottish ditty resounded sweetly all over the village of Northbourne. After that, the pupils being pronounced 'finished,' Jerry Blunt set forth, with his batch of performers, to London, where he got a fairly good price for his well-trained songsters. His birds sold off rapidly, each of them going off to be the pride and joy of some girl or boy's heart with the tuneful old melody-- 'O where and O where has my Hieland laddie gane?' and Jerry returned home with orders for many more bullfinches as he could procure. These orders, however, he was doubtful of executing; the finches were getting too advanced in age to prove docile pupils. Still, Jerry would do his best, and he set off to trap some young birds that had already left the parent-nests. The work of training these advanced birds was quite as difficult. However, Jerry was a persevering individual, gifted with wondrous patience, an untiring teacher. He succeeded beyond his hopes, and as time went on was enabled to earn what he called a 'tidy' sum. ''Tis wonderful strange, Jerry, my son, that ye can train the morsels o' critters to sing what we may call human tunes! Nobody, of course, could do it but yer own self, I'm sure,' grudgingly admitted his mother, when success became sure.