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and, when the lid is placed upon the outer case, of checking the draught of the fire, which is only continued through some small passages cut in the sides of the cylinder. A small opening also communicates with the fire from the outside, through which the former can be stirred when necessary.
“ In a boiler of this kind, many improvements could doubtless be suggested. Mr. Beck is of opinion that a great advantage would be derived by having the boiler, as in Rogers's improved, in the form of a dome above the fire, and by having the latter fed on one side by means of a shelving hopper, covered in, and placed as near as convenient to the top of the apparatus.
During the time in which this system has been in working, the water has never been within many degrees of the boiling temperature, yet the thermometer within the house has seldom, on the coldest nights, fallen below 60° or 65°. Its great advantages are, that the tank in which the water circulates will, with such modifications as circumstances may require, serve as a stage for plants, either in the centre or round the sides of a house, by which the expense of hot-water pipes will be dispensed with ; and its extreme simplicity, which is such that any person situated at a distance from engineers inight, with a little ingenuity and the assistance of a carpenter and blacksmith, erect an apparatus of his own; since any boiler which would create a circulation of water would answer as well as the one above described, although it might not be equally economical. We may also state that the atmosphere of the house in which this system is adopted is remarkably pure.” (Gard. Chron., Jan. 14. 1843.)
“I read with pleasure your notes at p. 19. of the Chronicle respecting a 'new plan of heating,' observed at Mr. Beck's of Isleworth ; and also that you do me the justice to ascribe the originality of its invention to me. As you have now brought it prominently before the public, perhaps a few observations from myself may prove acceptable.
“ It is a plan which can scarcely be recommended too strongly; for, not only is it adapted for the smallest propagating-house, but also for plant structures of the largest size. You have clearly explained the principle of the apparatus to your readers, therefore description from me would be superfluous. My tank or cistern is about 20 ft. long, and 5 ft. broad ; it is situated in the centre of a house, and, except at the end where the boiler is fixed, is surrounded by a walk. The boiler is one of Rogers's, and acts admirably. The depth of the tank is only 6 in., and this is quite sufficient. On the top I have placed large slate slabs, cemented to each other, to prevent a superfluity of steam from escaping into the house.
“ When first I thought of this excellent mode, I imagined that, to keep up a sufficient heat in the house, I should be obliged to retain a constant fire; but such is not the case. If the fire is lighted for two hours in the morning and evening, it is quite sufficient to maintain a steady and genial bottom heat ; as the large body of water in the reservoir, when once heated, remains warm for a considerable length of time. The thermometer is generally on an average at 65°.
“In a small house this principle can be adopted for less than 5l.; and in larger ones, at a cost at least one half less than that of hot-water pipes. As you justly remark, a common blacksmith and carpenter are all that are required to put it up. I doubt not but before many years it will be universally adopted by all those who grow pine-apple, melon, cucumber, or even stove and orchidaceous plants, when we shall find dung, leaves, and other fermenting materials excluded from the pinery and stove, and used only for manures. Even I, who can procure tan and dung at a very low rate, am a saver of at least 201. a year by this discovery; therefore the saving must be very great in a larger establishment, where hundreds of loads of dung, tan, and leaves are consumed annually,
“ On the 28th of December last the apparatus was set at work, and my foreman commenced propagating dahlias, which are potted and placed on the top of the slates, and surrounded by sawdust. They are now breaking luxuriantly; hundreds of cuttings are already off
, and plunged in sawdust in
another part of the tank. I have used the apparatus for more than eight months, and have been highly successful in striking some thousands of plants. It is certainly the most complete plan that possibly can be adopted for a propagating-house.” (W. E. Rendle, Plymouth Nursery; in Gard. Chron., Jan. 21. 1843.)
The idea of heating by a tank of hot water was put in practice many years ago in St. Petersburg by Count Zubow, and published in the Horticultural Society's Transactions in their volume for 1820, p. 430. The water was there heated by steam; but Mr. Rendle's, and also a mode adopted by Mr. Lindsay in the Hammersmith Nursery, are far simpler and more economical. Mr. Lindsay's method (see fig. 67. in p. 267.) is still more economical than Mr. Rendle's. We have also before us plans and a description of a very economical mode which has been adopted at Vienna, and which we hope to publish in due time. Pipes of earthenware are used about Paris, or brick fues cemented inside, as suggested by Mr. Beaton. — Cond.
Articles of Cream-coloured Clay. — Paving Tiles for Walks, and Edgings for Beds in Flower-Gardens, of a very beautiful cream-coloured and durable material, have been sent us by Messrs. Wyatt and Parker. How far the price may answer we cannot say, but in every other respect the improvement seems great indeed. We may say the same of a very beautiful name plate of this material, intended as a substitute for such plates as have been used in naming the trees in Kensington Gardens. The letters are black, filled into hollows indented by type, and afterwards burnt in; and must, of course, last as long as the material. Of course these name plates can be made of any size, and they are intended to be fitted into a cast-iron frame with a wrought-iron shank, with a disk on it either of cast or wrought iron. Whatever may be the cost of these earthenware labels at first, they are certain to be much cheaper in the long run than painted iron labels, which will require to be renewed every four or five years.
An Edging of Seyssel Asphalte, in lengths of about 3 ft., in thickness about 24 in., and in depth about 6 in., has been forwarded to us.
It has the great advantage of bending when slightly heated, so as to form curved lines of any description ; but its dark grey colour we are afraid will be somewhat against it, at least for a year or two after it is put down.
Palmer's Universal Steamer has been recommended to us by a head gardener as the very best cooking utensil he knows for a journeyman gardener's cooking-room. We have tried one, and found it a great improvement on the common tin steamer, and the price is very moderate. Any London ironmonger can supply it.
Palmer's Improved Economical American Oven is recommended by the same gardener, for those bothies where the men can afford to have roast meat. We should say that it will prove as valuable a utensil for the family of the head gardener, as the steamer will for his men. We have had a leg of mutton roasted in one, and also a loaf of bread baked, and found both excellent. The editor of the British Farmer's Magazine, speaking of the common American oven says: “ It is one of the most valuable inventions of the kind we know, and ought to be in every farm-house and every cottage in the kingdom. Our own family bread is chiefly baked in one of these ovens placed before the fire, and better bread there cannot be from any oven whatever. For roasting (not baking) small joints, we know nothing equal to it.” (B. F. M., as quoted in Supp. Cott. Arch., p. 1290.) One fault alone remained to the American oven, the inability of basting the meat, and the consequent unavoidable waste of dripping, which, owing to the extraordinary reflective power of the American oven, was so burnt and dried up as to render what little remained quite useless. To remedy this evil, the Palmer's improved economical American oven is so constructed as to carry off all the dripping and nutritious quality of the meat, hitherto wasted, into a dripping.pan, placed in such a position that the meat can be thence basted with the dripping without removing the oven from the fire, or interfering in any way with the progress of the cooking.” — Cond.
Art. II. Retrospective Criticism. The Study of Bees, and of Chemistry and Vegetable Physiology. (p. 576.) – I would be sorry if Mr. Wighton should think I undervalued the study of bees. I certainly did not mean to express myself in that way. He seemed, how. ever, from his manner of expression, by boasting of an ignorance of alkalies, to undervalue the study of chemistry. I certainly was not of opinion that his pretended ignorance was real, but thought it proper to defend the necessity of the knowledge of chemistry, to a certain extent, to gardeners. There may be differences of opinion as to the comparative space that chemistry ought to occupy in the education of a gardener ; but, certainly, it was not rating it too high, to wish a tithe of the time bestowed by Mr. W. on bees to be devoted to that purpose. His work lately published on bees bears evidence of its having originated in a vast deal of attention to the subject. In many situations, however, it may be found that a knowledge of chemistry is of more consequence, in others it may not; education should be as much as possible suited to the future prospects in life ; and much more attention may be required, in particular instances, to certain branches than to others. Gardeners, however, as at present situated, are subject to so many changes of place, that a very extensive course is required. When employers come to be better convinced of the benefits resulting, both to man and master, from a servant considering his situation as fixed, and thus being enabled to bring out the capabilities of the grounds intrusted to his charge (which a lifetime is generally short enough to accomplish), it may be more in the gardener's power to know to what branches of education he should most devote his attention. I do not recollect exactly what I said in the Gazette about excretions from roots. I am of opinion, however, that it is most likely the excretions from roots give rise to the fungi found there ; the fungi found there are more likely, as fungi in general, to feed on morbid excreted matter, than on the sound living tissue of the root: the subject, however, is open to discussion. As to the other parts of the essay, it is needless to make repetitions. I take the meaning of the word virgin soil to be, untouched; when pasture has lain long untouched, the soil may get consolidated so far as to regain the property inherent in virgin soil of keeping porous when made so, which no long-worked soil will do. This property, however, is quite independent of any substance contained in the soil; its good effects are more perceptible in light fertile loamy soils than in clayey, but it exists in all new soils; and, like a layer of charcoal spread on the surface, keeps up the proper communication between the soil and atmosphere, which is indispensable to fertility. It is a physical property belonging to its natural constitution, which gives effect to the mechanical operations of pulverising, which are soon obliterated in effete worn-out soils, by their tendency to dissolve into powder. This is quite independent of any organic matter accumulated in the pasture, or saline substances washed into the subsoil ; it is a natural principle in the constitution of the soil denoting vigour, while long working is productive of an exhaustion which no manures we can apply will altogether remove. The arguments I brought forward on this head in the former essay are what I have considered as solving the question in my own mind, perhaps better than I have been able to explain myself; but I am open to conviction, and may be mistaken, and there is nothing like proper discussion for eliciting the truth. The benefits pointed out by Mr. W. are great, but more in the power of manures to remedy; the other, nothing but time to consolidate, or trenching, will amend. I hope, however, that both essays will have been found beneficial as expressions of opinion, on which the readers of the Magazine will form a judgement for themselves. — R. Lymburn. Kilmarnock, November, 1842.
Art. I. Comparative Physiology. By R. LYMBURN.
(Continued from p. 470.) The roots of plants are peculiarly fitted for ramifying in the soil; they are not elongated by expansion like stems, but increase by additions from within to the point, and, not being confined in their developement by joints, ramify wherever they meet with obstructions, or food is found in abundance. They can enter the smallest crevices, and by the additions from within force their way onwards; and, when food is at a distance, the rapidity with which they elongate in quest of it is astonishing. When they meet with porous substances containing absorbed food, they ramify round them in all directions; and, in rotted leaves or well rotted manure, the fibres are always more abundant than in poor soil. The stomach of plants can only be represented by the soil. As the food of plants requires more decomposition than that of animals, a greater chemical power is found in the soil; and, as plants organise their tissues from nascent elementary substances, much decomposition is required, and the heat of the soil and admission of air cannot be too much attended to. Pitchers and other appendages may assist the general absorbing power, which is found on the whole surface of the plant, especially on the under side of the leaves ; and, in particular circumstances, this general power may take the place of the special absorbing apparatus of root, and may shadow out the possibility of digestive cavities becoming suitable for plants as well as animals. In as far however as practice is concerned, and for plants under general cultivation, the soil alone can be considered as the stomach; and the necessity of keeping this in proper order becomes at once apparent, and cannot be too much attended to. To keep up a proper degree of heat and moisture in the soil, a certain degree of porosity is required; and when the soil is dug deep in dry weather and
3d Ser. 1843. X.
broken small, and when the texture of the soil is such as to preserve that condition for a length of time, the powers of the stomach are such that a much greater effect will be produced, than in adverse circumstances where many times the quantity of food has been deposited. The same quarter of the garden or nursery grounds, especially if the soil is a strong loam inclining to clay, if cropped in separate portions and at different times, will have one part, which was worked dry and got a few dry days after working, producing an excellent crop, while another portion equally well worked and manured, which has unfortunately been subject to saturating rains before the particles of soil were dried sufficiently, will be found much worse. If small seedling crops have been sown there is frequently a total failure; and with stronger crops the growth is weak and yellow, compared with that where, the soil being worked dry and keeping open, the proper action of the stomach is preserved. It is in this way that turf buried, or deposit of roots left from previous crops, acts; or trenching of the soil and bringing up a new surface, which from long lying has recovered its powers of constitution, and is not so apt to run off into powder and close up the pores, as old effete long-worked soil does; it is from these deposits and the renewed constitution of the soil preserving an open porous state, that such astonishing effects are at times produced. I have often seen the crops twice as large from these circumstances alone, and the trees as large in one piece of the same quarter at one year's growth as in another piece at two years' growth, when there was no difference of the manure and other preparations. If the soil is too loose and sandy, or from long working falls into powder too easily, or if it is a strong clay not admitting of breaking freely into pieces, no manure will remedy these defects, unless deposited in such quantities as to alter the texture of the soil; and it is the same with good land, which has unfortunately been battered with heavy rains immediately after pulverisation, especially on clayey loams, which in good seasons and under proper circumstances often produce the best crops: Farm-yard manure acts much in the way of keeping the soil open and absorbing moisture, and this is one of the reasons why it will be found generally superior to concentrated manures, unless where carriage is expensive; by its gradual decay it keeps the soil porous: and concentrated manures will always be found of most value, especially those like guano containing much nitrogen, when mixed up with bulky substances, as sawdust of deciduous wood, peat-moss, scourings of ditches, or refuse of gardens, weeds, &c.
The changes on the substances absorbed by the spongioles of plants are probably confined to the rejection of insoluble substances, changes in the substances taken up being more proper