"Gardener," Chicago, Ills., asks: "Why is it, if steam is so superior to hot water heating, that none of the old gardeners knew of it. They seem to have run on hot water and never thought of steam ?"

Our correspondent is mistaken. Steam heating was used in Great Britain before hot water was thought of; and this was introduced as an improvement on steam. We believe the first hot water apparatus was put up by a Mr. Bacon, of Aberamen in Glamorganshire, in 1822. A Mr. Wm. Atkinson was the inventor. Steam had been used before.