of air-cells in their walls, to such an extent as to render them useless. When the clay is properly packed in, the cover shut down and secured, and the press put in motion, the wince is turned until the truckle-bed is filled-the cutting apparatus is brought down, and one pressing of the rough pipes is completed.

The smaller kinds of pipe must be handled by means of properly made forks, with extreme care, and placed upon a drying rack. If great care be not taken, the sides of the pipes will either fall together, or the soft clay will be pressed out of shape, and the passage more or less obstructed. The larger kinds are taken off the truckle-bed by hand, and set up perpendicularly for drying.

As all kinds of clay and loam shrink more or less in drying, this change of volume must be regarded in the pressing; and because different qualities of clay have different shrinkage in drying and burning; and because of the different degrees of humidity at which the clay is worked, and the different length of time the working is continued, and that of drying and burning required—all have their influence upon this shrinkage-no rule can be given of general application, and every manufacturer must learn by experience to give a proper length and thickness to his drain tiles. As a general thing, if the green tile are 13 inch in length, they will scarcely be 12 inches long when burned; and tile measuring 2 inches from outside to outside, when green, will not measure over 12 when burned.

Drying tiles is a matter of great importance, and special attention must be directed to this part of the manufacturing process. The tile to be good must be dried in a shed; in fact, a good shed is indispensable to the manufacture of tiles. The clay must be tough to retain its shape after running through the dies of the tile machine;

and such clay will warp and crack in drying, unless the process is conducted in the shade. If the manufacture goes on under a shed, no time is lost on account of rainy days, and the tiles, while drying, are protected alike from rain and sun.

A convenient arrangement of the shed is of considerable importance; in form, it is long and narrow, and must be so set as to allow the kiln to be put directly at one end, while the clay bank or pit and pug mill are at the other. Where it is intended to make from one hundred to one hundred and fifty thousand tiles in a season, the shed will need to be sixty feet in length by eighteen in width. It is not necessary to put up an expensive frame, a lighter structure answering equally well. Four sills, either of timber or plank, may be laid upon the ground, and leveled to receive the feet of the posts. The sills are laid parallel to each other, and lengthwise of the shed the inner ones ten feet apart, and the outer ones, one on each side, and four feet from the inner. The posts made of scantling, four inches square, stand upon the sills, making two rows on either side of the central space. The outer posts may be six feet in length, and the inner eight feet six inches, the tops being halved to receive the rafters, of two-by-four scantling. It is convenient. to have these posts and rafters of a uniform distance of six feet apart, through the whole length of the shed. The rafters may be tied together by three pieces of the same scantling, and these so placed as to give the best support to the roof boards, which lie lengthwise up and down the roof. The rafters and roof boards should be fourteen feet in length, so as to project about three feet beyond the outer posts; this is to prevent the rain from beating under and injuring the tiles. The supports for the shelves are narrow strips of board nailed to the scantling

posts, the top of one being eight inches from the top of the next. The shelf boards should be twelve feet long; they will then have a support at both ends; and in the middle they should be made of narrow but straight and well seasoned oak stuff, and laid loose upon their supports, and at a distance of about an inch from each other. The tiles dry better on these than upon wide boards. In this way the shed will have shelving on each side of the central space in which the tiles are made; each shelf inside the posts, will be a little more than three feet wide, which is sufficient for three tiles endwise in the green state; there will be nine tier of shelves, one over the other. A shed of this size will dry about ten thousand tiles at a time.

Through the center of the shed a railway track should be laid. This may be made of two-by-four scantling set endwise, and tied together by cross pieces, and sunk nearly to the level of the floor. Upon this a little fourwheeled car runs, carrying the clay from the pug mill to the tile machine, and afterward the tiles from the shelves to the kiln.

A shed something like what is described above is needed. where hand tile machines, similar in principle to Daines', are used. If it be intended to use Penfield's tile machine, which works by horse power, and has another arrangement for drying, scarcely any shedding is absolutely required. In this method, the tile machine being a fixture, drying carriages are constructed, and these are put on a track connecting the machine to the kiln, and are moved along as they are filled.

The internal arrangement of the shed should be such that the tile machine may be placed as near the center as possible. In the east and west ends of the shed "racks," as represented in the following cut, should be placed, on which to dry the tile. Tile should always be dried in the

shade-they dry more uniformly there than in the sun; beside, should inclement weather intervene, they are then protected. The rack is very cheaply and simply made; b is an upright, made of scantling, say, 3-by-4 inches, on which are fastened, with 4 or 5-inch spikes, the bats a, a, a, a; the slats or dryers, c, c, on which the tile are placed, may be of lath one-by-one and half inches. The uprights (b) should be no more than 6 feet apart-in fact, 4 feet is a good distance-in order to prevent the slats from warping, or "sagging," as the tile makers say.

The cut is intended to represent a rack to dry 16-inch tile; but it is best to make them wide enough, so that three tile may be laid on endwise. The vertical spaces between the slats c, c, or bats a, a, a, a, should vary with the size of the tile made-thus the distance from a to a should be greater for three than for 12-inch tile. When the tile are molded by the machine they are carried away and placed upon the dryers, as represented at d, d.

Or the drying racks may be conveniently made as fol

lows: Two upright posts of roofing lath should be fixed sufficiently far apart to permit one end of a drying board to go between them, and at the length of this board two more to receive the other end. When the tiles are cut off, they should be closely laid upon drying boards, the length of which should, for convenience, be about four or five feet, and the width equal to the length of the tiles. When the board is full it should be placed in the rack, upon pieces of scantling or other supports, and upon each end should be placed a similar piece of scantling, half an inch or so thicker than the tile, and upon these the next drying board filled is to be placed-the other supporting scantlings at the ends and drying boards upon them until the rack has been filled to the desired hight. The number of racks and their distance apart must be determined by the size of the dry house and the necessary movements between them.

Upon these racks the tiles remain to be dried, but they still require constant care and watching to effect drying properly. To keep the tiles straight, they should be placed close together, and if, in the process of drying, they become curved, the bow should be twined upward, so that they may assume their straight form again. The admission of air should be carefully regulated to dry the tiles uniformly; otherwise, they are liable to crack. In point of fact, the tile should be dried by the winds-not by hot southern winds, but cool north or northwest ones.

If the clay is well prepared, and proper attention paid to the pipes during the drying process, the remaining parts of the fabrication will go on well. The admission of air in proper quantity is always a matter of importance.

The larger kinds of pipe, which are placed upright while drying, should be reversed frequently, until hard enough to be laid down without injury, because the upper