hot water stoves, we shall speak of them freely, but by no means not approving of others we do not name.

In fig. 21, is seen the patented stove of Weathered & Cherevoy, No. 117 Prince street, New York city. (See fig. 21.) Figure A, is the stove, B, is the internal arrangement as heretofore made, and C, is their late improvement in the internal arrangement of the water spaces. At D, is seen a horizontal section just below the flue, which is the "top of the inside piece looking down upon it." In all the figures the water enters the stove, by the return pipe (b,) and leaves by the exit pipe (c.) This is an excellent stove. And as every propagating house must have a good heater, the prices are reasonable, ranging from the "smallest size $35," to "No. 5, $125."

Figures 22, show two forms of the stove of Hitchings & Co., 248 Canal street, New York city, (see fig. 22,) and the internal arrangement of their "combination cone and flue boiler, patented 1860." The water enters at (b) and flows out at (c). Their prices are "No. 1, grate 11 inches, $27,'", to "No. 5, 24 inch grate, $90," for the "conical boiler." And "combina. tion boiler," "No. 2, grate 13 inches diameter, $60," to "No. 5, grate 24 inches diameter, $130."

Either of these firms will, doubtless, give any further information that may be desired very willingly.

Other manufacturers could be named, but if the mode of heating the water in a water stove is not understood by these two plans we have described, the repetition of figures would not explain it any better.

At this point comes in, too, the price of iron pipe connecting with all such stoves, which is very heavy. Four inch pipe is the only practical. size, and costs from 80 cts. to $1.25 per foot according to the style, elbows, labor, &c., involved in fitting the house. "A house 125 feet long by 14 feet wide, for an early forcing house, would require about 800 feet of pipe," and by the job, "would cost about $600." He who heats by iron pipes. must pay a heavy bill. Hot water tanks, to be more fully spoken of, cost only about one-fourth, and where lumber is cheap, about one-eight as much as iron pipes and work as surely and easily as the pipe.

If not desirable to buy any of these stoves, we have known of small temporary inventions as a square box of copper, coiled tubing, &c., to be quite serviceable.

In examining these stoves it will be seen that the principle of any of these heaters is that cold or cool water comes by one end of the circuit of pipe to the bottom of the water stove, is heated, and hot water flows out through the pipe at the top of the stove, on account of its lessened specific gravity, and hence the necessity of some distance from the bottom of the stove to its top, as well as in the arrangement of the pipes, so as not to disturb this ascent, as the force is very small, yet powerful enough to make the water flow rapidly when rightly arranged. The water coming out of the stove circulates through the pipes, and in heating the propagating table and house, gives out its heat, and thus has its gravity increased, and by it falls to the bottom pipe of the stove. It is clear that the heat so obtained can be readily applied to a grapery, conservatory forcing house, and propagating table, or any like structure.

In fig. 23, (a) is the table containing the pots boxes and plants, and (b) is an enclosed space beneath containing four four-inch iron pipes, through which the hot water circulates. And fig. 24 is a ground plot (see figs. 23 and 24) showing the arrangement of the stove and the pipes. At (a) the pipe emerges from the stove (c) and ramifies back and forwards through the box as often as the owner pleases, and returns at (b) to the bottom of the stove or heater. This is the old style of propagating when high bot tom heat was supposed would not be endured by young plant roots. But since their love of a high heat has been proven, the pipes, as in fig. 25, may be laid on the table, and the (see fig. 25) equalizing material placed over them, and the pots and boxes with the germinating buds plunged with no partition between them and the pipes.

The pipes should not be less than two inches in their internal diameter; experiment has shown that cast iron four-inch pipes are the best. Only one objection can be offered to these pipes for the propagating table, and that is the expense. Everyway they are superior to hot air, or the brick flue.

3d. We shall name only one other method of heating the table. And that is the best, every way, notwithstanding all that can be said to the contrary. It is cheap, effective, and has the recommendation that should belong as far as possible to every agricultural implement, that it can be made by any one of common skill and energy in common carpentry. It is the hot water tank. Having had many enquiries by correspondents in different States, as to the tanks in use in the town in which I live, and their success, construction, and advantages; and the minute answer to these questions being at times quite a task, I hope the drawings and directions below will explain the subject. It is difficult to make even intelligent enquirers believe how simple they are, that nails, a few scantling, plank and boards are the materials, and that a common carpenter with his ordinary tools will do all the work, or that there is not some secret untold.

In fig. 26 is a section of the tank in, as I believe, its best form and (a) is the bottom of the tank made of the common machine plained, tongued and grooved, inch-and-a-quarter floor plank, pitch pine is the best, but any sound pine flooring will answer the purpose. The tank should be four or five feet wide. If four feet wide, then the flooring is to be cut four feet long; and when cut, nailed on to the side pieces (b, b) (sec fig. 25). It is not a matter of much importance how thick these sides are, 4x4 and 3x4 inches have been used, and two inches is thick enough, four inches is wide enough though six have been used. The length of these side pieces is as long as the table; or they must be joined so as to make the lengths required to fill the house. The way of putting a tank together is, to lay the side pieces b b) down on the ground or other convenient place inside or outside of the house, nail on firmly and tightly the bottom pieces (a) to the side pieces. Of course the tank when thus nailed is bottom side up. If the tongue and grooves, are coated with paint, or coal tar and linseed old mixed, they will last better. At one side of fig. 26, is represented a tongue put in grooves cut in the side pieces and the bottom boards; and on the other side a three cornered cleat or batten is represented nailed in the lower corner of the inside of the tank, coated with coal tar and linseed oil. Either way is good enough since after the first two or three weeks, tanks