« ElőzőTovább »
forms either ornamental or otherwise, and the variety is very great, let us examine the more practical principles of the
PROPAGATING TABLE. This cannot be made correctly without determining how it shall be heated, and the ends to be gained and accomplished by it. The table must be so high as easily to be reached, and the necessary work conveniently done on it. It must be as wide as it conveniently can be to give an ample space for the plants, and yet be easily operated, and four or five feet is that width, and it must also be as long as the house will admit of, and it must be stout enough to support the heat equalizing material, and the cuttings in pots or boxes of soil, sand and manure mixed for their growth. These are the plain and lesser items.
The more imperative demands of the table are, so to arrange it, that it can be heated from beneath, or have what is called bottom heat, as, for much of the time it is in use, the earth in the pots and boxes must be hotter than the air above the table. More of the success of propagation depends on this rule, than the uninitiated suppose. The heat of the table must be steady and permanent, yet not inflexibly so, for at night there must be a lesser heat than during the day. This is again a rule on which no small measure of the success depends. And the table and its contents must be very moist, and yet have a perfect drainage of all superfluons water. A point that cannot be safely neglected. Such are some of the obstinately imperious rules and conditions.
How can they best be met ? The answer in part is old and very plain, In fig. 16, the transverse section of the upper part of a table is seen, (see fig. 16.) In it (a) are the boards or planks of the bottom, inch and a quarter is ample thickness, supported by the four-by-four inch scantlings, (x, x, x). Wood, though not as durable, is better than any metal for the bottom, indeed we incline to the belief that wood and brick are the best materials for everything about the table. The side scantlings, (6, 6,) the one next to the wall of the house and the other next to the walk, should be two inches by four inches. Other dimensions may be adopted according to the method of heating the house and its size. If the heat be violent and subject to abrupt changes, as all flue heat is, the equalizing materials need to be thicker, and hence the side pieces (6, b) should be higher. If the house is unfortunately large and roomy, the air cannot usually be kept damp enough, and these side pieces of the table, must be higher still, that on them may rest the glass sash covers, which in that case must cover the plants on the table, so that the air immediately about them shall have moisture enough. But if the house is low and compact, and has little air in it, as should be the case, these injurious secondary sash may be dispensed with, for they certainly are both inconvenient and expensive, and attended with less success, than if the vast roomy house did not compel their use. If the house, as to the cubic feet of air in it is correctly designed, it keeps itself damp enough without extraordinary care, and with greater success in germination, which is the better plan. And (c) is a layer of white sand or other equalizing material, and it also serves to keep an even dampness under the cuttings in the pots, or boxes of wood, plunged in the equalizing material, which boxes and pots contain the germinating buds.
The equalizing, plunging, bedding, or whatever it may be called, material may be of various substances. Perhaps white sand, or whitish lake or river sand is the most common in use, and though a good material is not the best, for it heats too slowly, drains too slowly and is a dull lifeless article, and success though good, is not as great as with better articles. Sawdust is better, but has the objection, that it is not easily kept moist, the heat beneath the table dries the bottom so much that though water is plentifully showered on the top, it will not keep it wet through the whole inass. Tan-bark also dries very readily, yet can more easily be kept wet. I am not aware of the real value of all the mixtures in use. So far as I have seen use made of tan-bark, it has no deleterious influence. The article that suits me best is the refuse of a flax mill. This though it dries too much at the bottom, yet retains and imparts the heat and moisture very favorably to the plants in the pots and boxes, and is on the whole very admirable, the best article I have ever seen in use. Stable horse manure is excellent, were it not for the smell of the steam escaping from it by the applied heat. Perhaps one third each, of sand, tan-bark and horse manure will be found to meet the exigency; these everywhere to be had, readily mixed, and retain heat and moisture long, while slowly and steadily imparting it to the plants. So far the table; and the pots or boses plunged in the bedding or equalizing material. Next-
HEATING THE TABLE. On this my own opinions are very firmly fixed by observation, in favor of one method and that is the hot water tank. For ease of construction, efficiency of its heat, the dampness of its heat as opposed to the dry flue, steam or water pipes, its small cost, ready management, and certainty of its results, let others say what they may; it has no equal, nur even an approximation of success. But before describing the hot tank, let the other usual plans be named.
1st. The Brick Flue. One who has never seen a brick frue in a grapery, conservatory or propagating house, cannot easily be made to believe how long a distance or by what a crooked, winding circuit the smoke and other products of combustion, with the heated air that accompanies them, can be made to circulate, nor how, nearly level the flue can be laid. After the fires are once started, and the bricks of the flue become warm, the draft becomes so great that it will easily pass one hundred feet on an almost perfect level, and by a crooked, tortuous path as can reasonably be desired, and then ascend a chimney and escape above the top of the house with wonderful facility. This is one of the most common and useful methods of heating conservatories and other glass structures, and it is not strange that it has been applied to heating the propagating table. It is not necessary to figure a stove for either wood or coal, or the brick fire-box, or brick enclosed grate, by which coal is burned in these flues, for they are well known. . Fig. 17 is a section of a common green house flue. At (a) is seen a flue of brick, (see fig. 17), and covered by tile or specially made brick, wide, and long, and broad. The outside measures are, neglecting