house is to fill it with tobacco smoke, which is easily done by setting fire to a small quantity of tobacco, and shutting the house close up during the night.

When trees are regularly watered over their leaves and branches, the red spider will seldom do much injury; nor will the mildew extend much ; but when the mildew appears, it may be instantly checked by throwing over it a little dry powder of sulphur vivum, which is readily done with a hare's tail used as a powder puff.

In the application of heat I obtained the greatest quantity, and finest quality of fruit, under the following management: the house being heated by steam, with Hague's patent apparatus; the steam was got up in the morning by sunrise; and for the first month the temperature raised gradually, until the thermometer stood at 70 degrees Fahrenheit at mid-day. About the sun's setting the fire was banked up or withdrawn, and the heat suffered to subside during the night, taking care only that it did not get below 35 degrees. The second month the thermometer was raised to 80 degrees at mid-day, and gradually increased until the third month, when it was raised to 100 degrees, suffering the heat to decline at night during the whole time.

Being of opinion that a constant supply of fresh air must in every way contribute to sustain the grand object of the conservatory, I made arrangements on my steam apparatus to produce this, as is explained in my essay on the pine apple, and shown

the sketches in plate 13.; and I found it in every respect to answer my expectations.

To afford a more certain means of distributing water equally over the surface of the soil in the pots, and at the same time to support an equal evaporation, I placed a covering of small pebbles on them, which produced the desired effect, and preserved a neat appearance.

With the view to obtain the greatest quantity of fruit, and the greatest variety within a limited space, I tried various modes of training the trees; and having found the method represented by plate 18. decidedly preferable to every other plan, I conceive it useless to describe any other. By this mode, it must be obvious, no time is lost by cutting back in the first instance; the nourishment taken up is effectively appropriated, and with the least waste; the annual increase of the tree duly supported, and the surface of the leaves, and the fruit, all brought to the greatest possible exposure to the sun and air. Fig. 1. plate 13. represents the plant in its first stage. Fig. 2. the manner in which it is to be fixed or trained. Fig. 3. the second year; and fig. 4. the third year. The most complete steps for the branches are small iron rods painted, and fixed into wood stumps, driven into the soil. A reference to my former observations on the force and flow of the sap in trees will show the principle which determines the branches to grow as described by the sketches. The first summer after planting, some of my trees bore a fine fruit;

the second, all of them; and the third, from two to four dozen each tree, and which were of the most delicate and perfect colour and flavour.

Although nurserymen are always ready to furnish trees of any name that may be asked for, I have never been able to obtain any so described, as to be generally acknowledged by gardeners. I shall therefore not attempt the recommendation of any particular sorts; but one remark made to me by a gentleman, who grew fruit in greater perfection in the house than any other I ever met with, appearing to me to be well founded, I shall state it, viz. that those sorts of the peach and nectarine, which are furnished with blossoms of short and small petals, are more prolific than those which produce long and broad petals.

245

ESSAY

ON THE

CULTIVATION OF THE PINE APPLE, &c.

THE usual mode of cultivating the pine apple, in every way that it can be contemplated by a mind accustomed to the study of nature, must appear imperfect the success that has attended its growth, under the varied and extraordinary treatment it has been subjected to, shows it to be a plant more tenacious of life, and more patient of injury, than almost any other; but notwithstanding the uncommon powers of endurance with which this plant is evidently endowed, it must be subservient to the three grand principles which govern and determine the progress through life of all animals and vegetables, viz. food, climate, and lodging, and a due application and supply of these must be requisite to enable it to attain perfection.

By a recent publication entitled "The different Modes of cultivating the Pine Apple, by a Member of the Horticultural Society of London," it appears that Mr. Knight has made some important experiments on this subject; and although the

A

expectations of this compiler, as to the success of his mode of proceeding, are obviously not very sanguine, he strongly corroborates Mr. Knight's opinion, that the old method of growing the pine apple is far from being perfect.

The observations of Mr, Knight support the natural conclusion, that excess of bottom heat must be injurious to the growth and production of the pine apple; and he has very judiciously placed this plant in a situation and under circumstances to prove the effect of the other extreme, and unless the two extremes are ascertained, a medium cannot be fixed.

Mr. Knight expresses himself to be "much inclined to agree with Mr. Kent," that the bark bed is "worse than useless," and in pursuing this idea, it appears he has made some important demonstrations; he has shown that the pine apple may be grown without a bark or any other hot bed, and that it will endure a temperature as low as 32 degrees Fahrenheit; he also seems to have established the fact, that the pine apple, like all other plants, exhibits a greater degree of health, under the natural difference in the temperature of the atmosphere, as it exists between day and night, than under the unnatural continuance of the same degree of heat.

Alluding to Mr. Knight's opinion and experiments, it is remarked by the compiler of the before mentioned work, "that the pine apple will grow without what is technically called bottom heat, is an obvious truth, since no plant in a state of nature