reader is aware that plants will be prevented from suffering from want of water when the vacuity is filled, and from having so much heat as usual carried off by evaporation from the sides of the pot when the vacuity is empty. Such pots are peculiarly suited for plants in rooms, and they might be rendered clean-looking or ornamental by being glazed externally. Care should be taken, however, not to glaze them of a green colour, nor to endeavour to render them ornamental by coloured imitations of flowers, or other natural objects, for reasons that we need not here insist on. The colour may be of stone or brick, and the ornaments, if any, should be sculptures, not paintings. (See Quatremère de Quincy On Imitation.)

J

Fig. 16. Mr. Brown's Flower

pot with double closed Sides,

Saul's Fountain Flower-pot (fig. 17.) has hollow sides with a stopper, and it supplies the plant with water on the same principle that a glass fountain supplies a bird in a cage. An outer basin is made on the bottom of the pot, to which the water enters at a, and is carried round the pot in the basin, there being two or three

holes through the bottom of the pot, as seen at bbb. By these means the water is drawn up from the basin by the roots of the plants; or, if it should be desirable to prevent it from being drawn up, the exterior orifices of the holes which open into the basin or saucer can be closed. The fountain is supplied with water by taking out the stopper c, the entrance into the basin at a being at that moment closed; and, as soon as the water runs over

at c, the cork or stopper

Fig. 17. Saul's Fountain Flower-pot.

This pot is the inven

of that orifice is put in, and the stopper at a removed.

tion of Mr. Saul of Garstang, who sent the above description, and the sketch from which the engraving is made, on Dec. 5., and who informed us at the time that he had had them both some weeks by him.- Cond.

Stephens's Plant-protecting Flower-pot, with double Rim, of which fig. 18. is a section, was sent to us by Mr. James Stephens of Carr House, near Doncaster, a gardener who has read this Magazine from its commencement. It was sent in April last, but we did not receive it till Dec. 29. This pot not only supplies the plant with moisture where it is most wanted, but serves as a plant-protector, as there are but few creeping insects that will venture to cross Fig. 18. Stephens's Double-rimmed from one rim to the other when the space between is full of water. For plants that stand out in the open ground, Mr. Stephens has the pots made with two small holes, one on each side, half an inch from the bottom; and as there are no holes in the bottom, worms cannot get into the pots, nor can the roots of the plants root through these holes into the ground; advantages both of which are of no mean importance.

Flower-pot.

Mr. Stephens, though he invented these pots, has no pecuniary interest in them; they are manufactured by Robinson & Co., at Kiln-hurst, near Swinton Station, Yorkshire, at from one penny each upwards. Mr. Mearns of Leeds, and a number of experienced gardeners, Mr. Stephens informs us, declare this pot to be the most decided improvement hitherto made in flowerpots.-Cond.

A new Plough for raising Potatoes has been invented by Mr. David Goudie, overseer upon Hillhead Farm, near Kilmarnock. The implement somewhat resembles the grubber harrow, being held by two handles, drawn by two horses, and supported upon two wheels. Details will be found in the Kilmarnock Journal, in the Stirling Advertiser for October 14.; and the implement itself may be procured of Messrs. Drummond, Agricultural Museum, Stirling. Cond.

The Scotch Pine, a Substitute for Candle. Distillation of Oil of Turpentine from its Roots. - The Pinus sylvéstris, or native fir of Scotland, abounds with resinous matter and turpentine throughout its whole structure, which is particularly the case in the lower part of its trunk and roots. Dr. Howison, many years ago, when residing in and passing through various parts of the Russian empire, observed that the principal (or almost entire) light used by the peasantry in the northern departments was produced from slips or laths of the fir tree fixed horizontally, or in a slightly sloping direction, on iron stands, and set fire to at the lower extremity. These laths might be a yard in length, and of small diameter. Each one gave a flame of greater size than a candle, and continued burning for a considerable time, when its place was supplied by a fresh one. Might not the same method be followed in some parts of Great Britain? In the Highlands and northern islands of Scotland the peasantry use the extreme roots of the fir tree, dug out from the bogs and peat mosses, as a substitute for candle; and, in consequence of the quantity of turpentine contained in them, they burn with vivacity and splendour, furnishing a brilliant light. Around the cottages or isbas of the Russian peasantry Dr. Howison observed the large roots of the fir tree, dug from the earth after the trunk had been cut down for the numerous useful purposes to which it is applied, lying indiscriminately about. These were obtained previously to the falling of the winter snow, which remains for seven or eight months of the year. During the above period, when no other more valuable work can be obtained, the peasantry break them down into small pieces with hatchets, put them into a small still, and obtain oil of turpentine in large quantities at no expense, the exhausted slips, the refuse of the boiler, from which the turpentine has been already extracted, furnishing fuel for the future fire. The receiver is a glass bottle with a hole in its bottom filled up with a plug. When the distillation is over the plug is withdrawn, the water, falling to the bottom from its greater specific gravity, is allowed to escape, and the floating oil of turpentine is retained. The sale of the turpentine pays the expense of dig ging up the roots (which leaves the ground free for the plough), and allows a surplus for the labour. Might not the same be done by the unemployed labourers in some parts of Great Britain? - H.

The Stimulus of Competition in Agriculture. Our great manufacturers have thriven under the sometimes too feverish and intense, but yet generally wholesome, stimulus of competition. We think it can hardly be said that of late years this principle has been brought sufficiently to bear upon the growers of agricultural produce. We speak of them, as a body, with the highest respect; they are the very trunk of our social health and strength: may the day never come when they shall cease to be the first among the classes of the noble country they adorn! But to say that they require to be stimulated; to say that, unless stimulated, they will not use their utmost and sustained efforts to devise the means of economising production, and of selling as cheaply as possible; and further, that the stimulus they may afford to one another cannot, under all circumstances, be considered sufficient; all this is merely to say that they are men, and that they are not wholly exempt

from the common, the universal, infirmities of men. Let us look at the difference in private life between a frugal and a lavish expenditure; let us see how practically true it is, that equal means do not yield equal, but on the contrary yield most unequal, results; and we may then the more readily conceive that English agriculture has large resources as yet almost unopened, upon which it may draw in the time of need, and which will give ample scope for their exercise, before they have raised our average cultivation to the standard of the South-east of Scotland. (Foreign and Colonial Quarterly Review, as quoted in the Morning Chronicle, Jan. 14. 1843.)

ART. II. Domestic Notices.

ENGLAND.

THE new Royal Gardens at Frogmore, which have already excited much curiosity in the horticultural world, are progressing very satisfactorily, and bid fair to surpass all existing establishments of the kind. The splendid range of metallic hothouses and greenhouses, which, when completed, will be nearly a thousand feet in length, begins to make a very conspicuous figure, several of the most able workmen in the employ of Jones and Clark of Birmingham (the contractors for the horticultural buildings) having been for many months past actively engaged on the spot. The west wing of the range, to the extent of more than 300 ft., is already nearly completed, and the corresponding portion on the other side is being rapidly proceeded with. In the centre of the range is a neat Gothic structure, designed for the residence of Her Majesty's gardener, and it is intended to form a noble terrace or carriage drive in front of the buildings, which, commanding a view of the entire range, will produce a very striking effect. When the several works now in hand are completed, they cannot fail to attract a large number of visitors, and particularly such as take an interest in horticultural pursuits. (Sun.)

Bicton Gardens in February, 1843.I have now been a week in Exeter, and twice to see Mr. Barnes. The weather here is at present dry and seasonable; wind N. and N.E., with very slight frosts in the mornings; and there was a slight snow-storm or two at the beginning of this week. I am told there has not been here this winter sufficient frost to kill scarlet geraniums, petunias, Sálvia fúlgens, and such like things. Where they are under the sheltered walls, they have kept flowering all the winter; as well as mignonette and many other things. Of course the soft free-growing plants in the open flowergarden were cut with the slight frost in the autumn, at the time the dahlias were cut. Camellias out of doors have flowered beautifully all the winter, as well as many of the beautiful scarlet and pink rhododendrons. Mr. Barnes informed me that a large plant of Rhododendron Nobleànum in the flower and American garden had on christmas day above 200 heads of bloom fully expanded; but the cold winds this week have turned some of them a little brown. The peach, apricot, and pear blossoms on the walls are getting very forward. I hope this fine but cold weather is in time to retard and keep things in their places. Mr. Barnes says he never found the ground to work so well as it does this season. There are still excellent pine-apples here, and a good succession coming on. I think I never before saw such a show of pine-apples, at this season of the year, as are now coming on here. The peachhouse presents a splendid assemblage of blossoms, and the fruit seemingly setting well. Mr. Barnes's new potatoes are thoroughly ripe, and he has a good crop. Mushrooms, cucumbers, French beans, asparagus, &c., have been very abundant all through the winter, and still continue so. It is really very interesting to be amongst the plants here: the houses are very gay with bloom, and the plants are very healthy and vigorous. Heaths are growing like weeds. The camellia blossoms I never saw so large and perfect in form before. Mr. Barnes has grapes as large as marrowfat peas. The kitchen

garden has been turned upside down this winter, the whole of the box having been taken up and replanted in a regular manner: 500 cubic yards, equal to as many cart-loads, of marl and loam have been got in for the borders, &c., the greater part of which is already trenched in.-W. Exeter, Feb. 11. 1843.

The Lane-End Horticultural Society, exclusively for the encouragement of horticulture among labouring cottagers, is well worthy of imitation throughout the country. Premiums are offered for the first and second best cultivated gardens, and for the first and second best of all the commoner vegetables, fruits, and flowers. The premiums vary from 1s. to 5s. The place of exhibition is the schoolroom, and the clergyman and the schoolmaster are the principal judges.

The Chislehurst Horticultural Society for Cottagers is conducted on the same general principles as that of Lane-End, and is effecting for part of Kent, what the other is for part of Bucks. Very handsome premiums are given by the Chislehurst Society, and the Messrs. Barnes, and other first-rate gardeners, not only subscribe liberally, but contribute improved varieties of culinary vegetables, &c.-S. T. Feb. 1843.

ART. III. Retrospective Criticism.

PROFESSOR Henslow's Lecture on Manures.-I have your favour of the 27th instant, and the two Ipswich newspapers containing Professor Henslow's lecture on manures, and feel obliged by your attention. I have little to remark on the essay. Professor Henslow is cautious and prudent in his statements, and I agree generally with what he says. A great many, even of physiologists, seem to be of opinion that carbonic acid is the sole way of plants getting their carbon. This, I have no doubt, is the principal form in which they get it, though humic acid and organised substances, I think, cannot be excluded. If sugar, gum, and starch are stored up in the plant, to become again the food of buds in the spring and of seeds, does it not show that these and similar substances may be made useful? When soluble in water, and absorbed, where can be the difference? In seeds germinating and buds sprouting these substances are changed into carbonic acid; which, losing its oxygen in the leaf, gives rise to the nascent carbon of DeCandolle, necessary in forming the latex or blood of the plant which alone can furnish the products of assimilation; and what will prevent absorbed substances from being so transformed by the vital activity of the plant, as well as the same substances stored up in the autumn, and restored to the circulation in the spring?* The professor seems to lean to the opinion that the carbon is mostly taken up by the roots: he says carbonic acid and carbonate of ammonia are got from the air, and that they are absorbed by water, and carried into the soil, which is quite different from getting carbonic acid altogether by the leaves. If the carbonic acid is taken up by the roots, then there is some reason for depositing carbon in the soil; if wholly got by the leaves, and the atmosphere always contains the same proportion, then we may as well spread the carbon on the roof of the house as deposit it in the soil.

The professor seems to lean to the opinion that manure is best deposited unrotted. If we were sure of its rotting equally well in the soil, if the moisture and heat of the soil could be regulated so as to insure this, it would be an advantage. The contrary, however, is most often the case;

* If organised substances are divided small enough to allow of their entering the spongioles of the root with the water, which they will do if soluble, the decomposing powers of the plant are sufficient to reduce these to the elements of food, as well as sugar, gum, starch, &c. If nascent carbon is needed, as well as nascent hydrogen and oxygen, the carbonic acid of these substances will furnish it as well as that of the soil or air.

and, as he himself says, the crop planted with fresh unrotted dung loses the benefit, and much is lost before another crop succeeds. The chemical preparation, or digestion, of the manure intended as the food of plants is, undoubtedly, best done in the rot-heap. If carefully managed, covered with mould, and kept as directed in the last essay, there should not be so much loss as the professor states, one half of the nitrogen. It is not convenient at all times to deposit fresh manure, and the carriage is much more expensive. If the heat is well kept down by frequent turning, and the washing away prevented, there should not be much loss. Putrefaction and fermentation are much more active in the heap than in detached portions. Fresh manure in the potatodrill, unless the season is moist, is often found quite fresh at the end of the year.

On the subject of nitrogen he notices only that got from the nitrogen of the manure in the state of ammonia; but this, though undoubtedly the principal, is not the only source of nitrogen. If, as asserted by Dumas and others, animals do not absorb nitrogen from the air, their nitrogen being wholly got from plants, it follows there must be some source of supplying the waste. Accordingly we find that, in the combustion of coal and wood, the hydrogen given off forms ammonia with the nitrogen of the air already deprived of its oxygen by combustion; and part is found deposited in the soot in the form of carbonate of ammonia, or sulphate, when the substances burned contain sulphur; part of the ammonia will also escape into the air: and thus combustion is a great source of nitrogen to plants, as in soot, gas liquor, &c., besides that to the soil by rain. Volcanoes are also a source of ammonia on a large scale, as noticed by Professor Daubeny. The eremacausis of Liebig (or slow combustion of substances) is also another source. Where the oxygen is partly got from water and partly from the air, the hydrogen set free in the one case, and the nitrogen in the other, will form ammonia. Professor Johnson seems to think that much of the ammonia said to be absorbed by charcoal, &c., should be ascribed to this source rather than to absorption. In the manure heap a good deal of the ammonia found is probably due to this source, as well as that of the nitrogenous substances it contains. Nitrogen is also soluble in small quantity in water; and the water of the soil absorbed by plants will, no doubt, afford a small portion of nitrogen. The common air absorbed by plants, and deprived of its oxygen by absorption, is another source, as noticed in our last essay. From all these sources the nitrogen is supplied to plants in sufficient abundance to enable them, on the other hand, to supply the wants of animals, which are now generally believed to be consumers rather than producers of nitrogen: they give it off principally by the urine, showing the great benefit of retaining this in the manure heap; but also waste it by perspiration and exhalation, as shown by the fetid smell of both these excretions.

Dr. Madden is of the same opinion as the professor, that sulphate of ammonia is very apt to be re-acted on again by carbonate of lime; and sulphate of lime and carbonate of ammonia are the result. If soils contain much lime or chalk, the benefits of urate or sulphate of ammonia may be greatly lost by this cause. Sulphuric acid is said to be as cheap in proportion as gypsum, where needed; but carbonate and humate of ammonia we should consider more beneficial to the generality of plants, though such as clover, pulse, &c., are more in need of sulphur.-R. L. Kilmarnock, Dec. 30. 1842. Charcoal and Charcoal Dust. In your Vol. for 1841, p. 254-5., it is said, speaking of charcoal and charcoal dust, that M. Lucas was the first to show the action exercised by the charcoal on vegetation; thus setting aside the Italians, among whom the Abbé Piccone and Professor Moretti have treated of it at length in vol. 2. of the Biblioteca Agraria, p. 70.—Giuseppe Manetti. Monza, Dec. 7. 1842.

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