Let me here introduce an anecdote of a fly communicated to me by a friend to whom I am indebted for some other remarks. Many years since, I believe about forty, Slingsby, the celebrated opera dancer, with whom I was acquainted, resided in the large house in cross-deep, Twickenham, next to Sir Wathen Waller's, looking down the river. He was, like the author of the 'Gleanings', fond of the study of Natural History, and particularly of insects, and he told me that he once tried to tame some house-flies and preserve them in a state of activity through the winter. For this purpose, quite at the latter end of Autumn, and when they were becoming almost helpless, he selected four from off his breakfast table, put them upon a large handful of cotton, and placed it in one corner of the window nearest the fire-place. Not long afterwards the weather became so cold that all flies disappeared except these four, which constantly left their bed of cotton at his breakfast time, came and fed at the table, and then returned to their home. This continued for a short time, when three of them became lifeless in their shelter and only one came down. This, Slingsby said, he had trained to feed upon his thumb-nail, by placing on it some moist sugar mixed with a little butter. Although there had been at intervals several days of sharp frost, the fly never missed taking his daily meal in this way till after Christmas, when his kind preserver having invited a friend to dine and sleep at his house, the fly the next morning perched upon the thumb of the visitor, who being ignorant that it was a pet of his host's, clapped his hand upon it, and thus put an end to Mr Slingsby's experiment.
Edward Jesse, 1834, Gleanings in Natural History