In all establishments of any pretension, we have numerous structures for the cultivation of fruits, but, amongst modern inventions, there are none so useful to the amateur as the orchard house, which was brought into existence by that excellent fruit cultivator, Mr. Rivers, of Sawbridgeworth, Herts., to whom we are also indebted for much valuable information on fruits, and for the introduction of many new varieties. The orchard house is for protection from severe spring frosts, such as we have had of late years. Mr. Rivers's first houses were erected against some old yew edges, which formed the back, and these houses were found to answer their purpose to a certain extent, in the cultivation of the more hardy fruits, such as plums, etc.; but Mr: R.'s later erections are constructed with boarded sides. The first cost of such houses certainly would not be much, but I think they will eventually be found dearer than properly built brick and mortar walls. Most orchard houses hitherto erected, are without any heating apparatus, which I also think is false economy; for the plants in such structures must naturally be forwarder than those out of doors, and the frost has much power in a house of this sort, if means are not taken to keep it out; but it must be borne in mind, that orchard houses are a new invention, and far from that perfection which we may expect they will ultimately reach.

My idea of a good house is, that it should be built span-roofed (say twenty feet wide), and as long as the proprietor pleases. The height from the ground to the eaves should be about six feet, the lower three feet of which should be of brick, and the upper of glazed sashes, made to open, for the purpose of ventilation. A three-feet border, in which trees may be placed, might run round the house; and the path should be three feet wide, which would leave eight feet for the centre border. The fine, or hot-water pipe, should be placed'on or in the path. It has been the practice, hitherto, to grow the trees in pots, several nurserymen having prepared many trees well furnished with bloom buds for that purpose, and thus secured a crop of fruit the first year; but how this method will succeed, is at present a matter of uncertainty. For my part, I am very doubtful of its propriety, as I fear the trees will not continue to produce good crops many years, if grown in pots, while, if planted in the borders, success would be certain, as they may be kept dwarf by proper pruning, and removing and root-pruning every two or three years, which might be done without at all injuring them.

Another means of keeping the trees dwarf, is the proper selection of stocks to work the different fruits on, as, for instance, the Pear on the Quince, the Apple on the Paradise, the Cherry on the Mahaleb, and the Plum on the Black Thorn. Most fruits may be successfully grown in an orchard house, including Apples, Pears, Peaches, Nectarines, Plums, Apricots, Grapes, Figs, and Strawberries, besides what may be had in the way of choice flowers and vegetables; and thus it will be seen that the amateur possessing one of these structures, may command a good variety of fine fruits at but little expense. With regard to the management of the orchard house, every attention must be paid to proper ventilation, which is most essential, and provision must be made for admitting air both by the side and top lights. If the side lights can be all removed, sufficient air may be given without allowing cold draughts, by keeping them closed on the side the wind would enter. Watering must also receive due attention, as the trees might be soon damaged either by an excess of moisture or the want of it.

Another important point is to keep the trees properly pruned and the fruit properly thinned, removing all that is not required as soon as it is Bet, before it begins to damage the trees.