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verses over two drains, the one placed at the back and the other at the front. These fire bars traverse at the rate of about 6 ft. per hour, and only require a power about one thirtieth of a horse to keep them in motion. The fuel being introduced on the bars at the entrance, through a hopper, is carried onwards by the traversing motion of the bars, passing through all the relative stages of combustion until nothing but the scoria or unvolatilisable portions remain, which are rejected at the back. It will be seen that in this arrangement, when the fuel is first introduced, it parts with its more volatile portions, which are consumed with the fuel farther advanced on the bars, and consequently in a more perfect state of combustion. By this process all the carbon is burnt, instead of being distributed in the atmosphere, which is at once seen by the total absence of smoke in the chimneys of the furnaces where it is employed. This is of itself a great saving in the economy of fuel ; but another equally important is in the fact, that the coal dust or refuse coal answers all the purposes of the largest and best coal. Through the constant admission of atmospheric air between the fire bars, the heat of the furnace is constant and uniform, and there is no clinkering of the bars, which come out of the fire as clean in the evening as they did when they entered in the morning. The hopper, which supplies the fuel, may be made to contain a supply of fuel for an unlimited time ; and thus the regulation of the fire is rendered quite independent of the caprice or neglect of the stoker.

This furnace appears to be interesting to the gardener in two ways: Ist, because the general adoption of some such arrangement, where the important object of effecting the combustion of smoke is accomplished, would tend greatly to improve the purity of the atmosphere, and prove beneficial to the cultivator; and, 2d, as it might be economically and advantageously employed in heating houses upon a large scale, particularly with the hot-water apparatus, – A. B.

The Tree-Creeper (Cérthia familiaris) and the Green Fly that infests Geraniums. — Once upon a time one of the little birds called tree-creepers entered a small greenhouse, and took up its abode therein for a day and a night, at the end of which time it had cleared the plants of insects most completely. Not a leaf nor a twig escaped its searching glance. As its scientific name implies, it was quite tame and familiar, and never seemed to heed the intrusion of strangers, but still continued to carry on its work of destruction. But, alas ! on the second morring the voracious little bird was found lying stiff and cold in the corner which it had fixed on for its bed, having, in fact, glutted itself to death. Gardeners, if you wish your greenhouse plants to be free of insects, encourage the Cérthia familiaris when you have it, and try to procure it when you have it not. — A. S. M. Braes of Gowrie.

Wireworm destroyed by the Mole. - A singular instance of the utility of protecting the mole has within these last few days come under my observation. Having had occasion to turf up a number of small clumps in our flower-garden, I was astonished in a few days to find that the moles had pushed up the turf over the whole surface of some of the clumps. I immediately searched for the cause of their visit to these patched up clumps ; when, to my astonishment, I found the wireworm in great abundance between the surface of the former clump and the new-laid turf. They had, I suspect, been in the turf before it was laid down, and, the ground beneath being beat so hard, they could not penetrate farther; where the moles, having once discovered them, seemed determined on eradicating them. They were mostly the larva of Agriòtis lineatus, with a few of A. obscùra. What was very singular in this instance is, that before this time I never saw a single indication of a mole in the garden, although there were plenty of them in the wood which surrounds it. – John Dunlop. Worcester Park Gardens, near Kingston, May 10. 1843.

Cytisus Adàmi, Purple Laburnum.— I write to communicate to you a further freak of this singular plant. The tree of my brother, Mr. Algernon Herbert, at Ickleton, near Saitron Walden, having for some years ripened seed on both the yellow-flowering branch and the small-leaved purple-flowering

branch, has, this year, in addition to these eccentricities, produced small solitary axillary purple flowers in that part of the tree which has retained the original hybrid character. Some of the seedlings from the yellow branch have flowered, and are natural yellow laburnums. One from the small purple branch at Spofforth has rounder leaves than Cytisus purpùreus, but has not yet flowered. I regret the loss of one seedling from the yellow branch, which showed a purple tint on the young wood, and would probably have manifested some diversity in the colour of its flowers. The habits of this plant are not those of a seminal mule; and I entertain little doubt of the correctness of my surmise, that it was produced by the cooperation of the cellular tissue of the two species in forming the bud on the suture where the bark had been inserted in budding. - W. Herbert. May 18. 1843.

Johnston's improved portable Garden Engine (fig. 76.) is formed on exactly the same principle as that of Mr. Read, figured in our Volume for 1837, p. 459. The principal difference is, that Mr. Johnston occupies two cylinders with what Mr. Read includes in one. The following is the description sent us by Mr. Johnston. On raising the handle a, the water passes up the lower tube, opening the valve b, and filling the tube c. Depressing the handle closes the valve b, and opens the valve d; the water passing up the tubes e and f, and compressing the air in the outer tube f, when it continues up the tube e to the joint g, through

í which it passes out at the jet, with or without the rose h; the joint being movable up or down. On the handle being raised again, the valve d closes, and the valve b opens for the water to fill the tube c. At the same time that the tube c is filling, the air compressed in the tube f is expanding, and forcing the remaining water in the tubes e and f to flow out of the jet. This process being repeated at each stroke of the pump, causes a perpetual stream, which may be thrown out 60 ft. The conducting tube k screws off at i, rendering the instrument extremely portable. The instrument itself is very handsome, and well adapted for lady gardeners. — Cond.

Cicer arietinum L.-I send you some seeds of Cicer arietinum collected at Athens in 1842. It is an excellent vegetable, and remarkable when growing for the whole plant being covered with a secretion of oxalic acid in a liquid state. I never saw it in crystals, as stated in the Penny Magazine. — W. C. 1. May Fig. 76 Section of Joka, 13. 1843.

ston's improved portable

Garden-Engine. Improvements in Garden Pots. — In a valuable article on this subject in Paxton's Magazine of Botany for March, the glazing of pots is objected to as assimilating them to culinary utensils, and as interfering with the pictorial effect of vegetation, for which a dead or dull quiet surface is justly said to be much more appropriate than a shining one. “In reference, however, to the health of the plants, experience is most decidedly in favour of the hardest pots. The less porous the material, the less likely is it to become sodden or saturated with water, or to carry off moisture with too great rapidity in the burning heat of summer. Soft thick pots that are imperfectly baked are universally discarded by good cultivators, and those which are hardest and thinnest preferred. Pots or tubs of slate are found, likewise, to be excellent receptacles for most plants ; and hence we discern nothing but that which is fitted for proving beneficial to plants in the idea of glazed pots ; but, as their hardness and closeness may almost be realised without the glazing, we deprecate their use on account of the appearance.” (p. 42.)

The author after nocicing Mr. Brown's hollow-sided pots, which he thinks

(with the improvement of the hole for the admission of the water made outside the pot instead of inside) are particularly suitable for plants which require a great deal of water in summer, and whose foliage is not low, or ample enough to shade the plants from the rays of the sun, such as Tropæolum tricolòrum and T. brachýceras, suggests three improvements. These are : less depth in proportion to the width ; a better drainage by means of more holes in the bottom; and the admission of air through the drainage holes, by raising the pot above the surface on which it stands by means of feet, or, in other words, carrying down the sides of the pot an inch or two below

the bottom, and making two or three notches in the prolonged part. “ That shallow pots are of the utmost importance to fiowering plants in promoting their beauty, every day's observation more and more fully convinces us. No gardener would now think of letting his vines or his peach trees have a border as deep as it is broad, or, in other words, suffer their roots to extend downwards as far as they do horizontally. He would at once anticipate (and justly) a failure in his crops from such a proceeding. And yet the cultivator of exotics takes a course which is quite as unwise when he puts his plants in pots that have the same depth as diameterThe grand rule in all culture, whether for fruit or flowers (for the means that will produce the former must bring the latter), should be to keep the roots near the surface ; and this can only be done by positively preventing them from descending, for it must be recollected that all roots have naturally a downward tendency. In order to accomplish this end with potted plants, there is no other way of proceeding than by making the pots shallower; and in this, we are persuaded, lies the art of flowering plants quickly and well. It will repress straggling and rampant habits, and, with a state of beautiful dwarfness, produce an unusually liberal flowering condition. We are greatly mistaken if the Chinese are not better philosophers than we are on this point ; for we believe they plant their curious stunted trees in exceedingly shallow pans of porcelain.” (p. 44.)

Hunt's improved Garden Pots and Saucers, of which figs. 77. and 78. are specimens, are well calculated to accomplish two of the desiderata mentioned in the foregoing paragraph, viz., improved drainage, and the admission of air ; and they are also adapted to prevent the entrance of worms. Fig. 78. shows a pot

Fig. 77. Hunt's improved Saucer. with the improved bottom, which may be used with or without a common saucer; and fig. 77. shows the improved saucer, with which any common pot may be used.

Fig. 78. Hunt's improved Garden Pot. Two or three holes in the bottom of the pot instead of one, and an increased width in proportion to the depth, would, as the writer in Paxton's Magazine observes, be great improvements to these pots, and we have no doubt they will be made without delay by Mr. Hunt. Even as they are, they are obvious improvements on the common form; and the additional cost, when made of the common material, is only 1s. 6d. per cast. Ornamented pots this kind, ade either of the common material, or of a beautiful cream-coloured clay obtained from Teignmouth in Devonshire, are also manufactured by the same parties. For greenhouses, and for plants in rooms, this last description of pot, combined as it is with the improvements described, will be a great acquisition.

3d Ser. - 1843. VI.

Y

The new Method of potting Plants, or One-Shift System, promises to be the greatest step ever made in the progress of pot culture. A previous advance was made forty or more years ago, when the frequent-shift system was adopted instead of annual shifting or repotting. Previously, plants in pots were seldom shifted or repotted oftener than once a year, except in the case of balsains and a few other tender annuals, which received two or three shifts. Subsequently these shifts became much more frequent, so that when a balsam or a cockscomb was required to be grown to a great size, it was first planted in a pot of an inch or two in diameter, in rich finely sifted soil, and gradually shifted, as soon as the roots reached the sides of the pots, from one pot to another a little larger, till at last, when nearly full grown, it was in a pot of a foot or more in width. A similar practice was general with all plants whatever, even including heaths, that it was wished to bring forward rapidly. The results of this mode of culture have in general been highly satisfactory, and the chief objection that can be brought against the system is, the time and labour required. A second objection is, that water does not escape so freely, and consequently air does not follow it so readily, as when plants are growing in the free soil. This last objection is completely got over by the one-shift system, the essence of which consists in the employment of rough, turfy, lumps of soil along with fragments of stone, wood, charcoal, or other matters which keep the soil thoroughly open, placed, of course, over abundant drainage.

The one-shift system is said to have been first “struck out" by Mr. Wood, late foreman in the nursery of Messrs. Backhouse of York, and for the last two years foreman in the nursery of Messrs. Henderson of Pine-Apple Place. The dawn of Mr. Wood's invention may, perhaps, be found in Mr. Knight's chopped green turf (Physiological Papers, p. 243.), and Mr. M'Nab's “widemeshed riddle” and large pots or tubs (Cape Heaths, p. 20. and 23.); and, from the Letters on Bicton Gardens in this Magazine, and the Suburban Horticulturist, p. 616. and 706., it appears that Mr. Barnes has been in the habit of using rough, rooty, unsifted soil in potting for upwards of twenty years. The following account of the invention by Mr. Wood is from an excellent article in Paxton's Magazine of Botany for March, 1842. “ It appears to have occurred to him (Mr. Wood] that, as plants flourished with such amazing vigour when planted out in a bed, and, if judiciously exposed and drained, flowered also in the greatest profusion, it would be a most desirable object to give them the same means of attaining an early and luxuriant maturity in pots; seeing that, in many places, there is no convenience for having appropriate borders or beds in plant-houses, and, where there is, the specimens cannot be so easily controlled, nor are they at all portable. Numerous experiments, both casually and designedly made, had shown that, by the coinmon way of potting, no such ends could be brought about ; since plants which were placed in pots very considerably larger than those which they seemed to require almost invariably suffered, to a greater or less degree, from the stagnation of water in the soil. And, as this accumulation evidently formed the chief obstacle to the adoption of large pots for the smallest plants, it was very justly thought that any thing which could be employed to drain effectually the entire mass of earth, so that no water could stagnate therein, would give the means of allowing young plants in pots all the benefits which they would derive from being planted in beds. Following out this notion in a practical manner, small specimens were shifted from what are called 60-sized pots to those which were 9 in. or 1 ft. in diameter; using a turfy fibrous soil, divested of none of its rougher matters, and mixing with it a quantity of broken sandstone, in pieces from a quarter to half an inch square. By the united aid of the turfy and vegetable matters in the soil, and the fragments of stone scattered throughout its substance, it was thus kept porous and open, without even a tendency to become hardened, consolidated, saturated, or sour ; and the plants throve in it with the rapidity and health of those which were placed in a border, while, being situated nearer

the glass, and more subjected to the agency of air, &c., they began to flower much sooner, and more abundantly.” (p. 37.)

After pointing out the great advantages which will attend this system of potting, the following judicious practical details are given.

" The main point to be observed in potting plants, according to this as well as the customary mode, is to drain them thoroughly. To do this properly, it is requisite that a thick layer of broken pots or ashes, or some such material, be put in the bottom of the pot, and not merely a few pieces of potsherd. There should be at least an inch of drainage, and over all this should be sprcad a small quantity of dry moss, or a few lumps of very turfy peat or loam, in which all the vegetable matter is dead, but which contains a good deal of woody fibre. Either of these substances will assist the passage of the water, by preventing the fine earth from getting down amongst the drainage and stopping up its interstices, while they will also, by retaining some degree of moisture in themselves, keep the roots cool and damp whenever the earth happens to get excessively dry. What is of nearly equal consequence is the texture of the soil. It should by no means be reduced, pulverised, or sifted, any more than as the first of these may be needful. Vegetable fibre, and stones that are not too cumbersome, should be suffered to remain. Where heath-mould is employed, it ought to be full of roots, and be left, to a large extent, in rough irregular lumps, about an inch or so in breadth. There is infinitely too much preparing and manipulation in most composts; and the freedom with which heaths root into lumps of turfy peat shows at once that they would be more at home if potted entirely into something approaching to the natural texture of the soil in our heatheries or moors. The same principle will apply to all soils, and this constitutes a valuable part of the system of potting we describe.

A further part of the plan is to keep the neck of the plant, or that portion of the stem next the roots, rather higher in the pot than the level of the soil. This is often done with heaths, and is just as useful to other fine-rooted species. It keeps down exuberance, and promotes inflorescence. It saves many a delicate plant from being killed by water ; while, by maintaining the vital part in a drier state, it makes them less sensitive to the sudden and casual occurrence of cold in the winter.

“ But the process most conducive to the bushiness of the plants is the frequent reduction of their young shoots. This must be very rigidly attended to, when they do not of themselves bear a sufficient number of laterals. It may be that the branches will require stopping three or four times in the first season; but this will occupy very little time, and is of such extreme moment that without it not a few plants would be quite unsightly, whereas, with its aid, they have become the most ornamental of our exotic decorations. Where it is rightly practised, it will almost necessarily cause the removal of all the early flowers ; but with those plants that do not need to be thus treated, and with others that continue to show their blossoms despite such pruning, it will be highly advisable to take away all the flower-buds as fast as they appear.

" As to the application of the system, it embraces all flowering shrubs, whether belonging to the stove or greenhouse, but more especially those which have not been produced by art. Heaths, pimeleas, lechenaultias, &c., have all been found to be vastly benefited by it. At present it is not known how long specimens so managed will last after they have begun to flower. We should presume, however, that they will continue in beauty for three or four, or more years, with only a very trifling shift each spring, after the second season, and that they may then be discarded, to give place for similar progeny. The beauty of a greenhouse or stove does not consist in having very large or very old specimens, but in keeping plants of a moderate size that are particularly healthy and lavishly prolific of Howers." (p. 41.)

In a subsequent article in Paxton's Magazine, by Mr. Wood himself, we have the following concise and systematic definition of his system.

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