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In table No. 10 the results for each year are grouped so that a comparison can readily be made of all the nothing flats and all those receiving special fertilizers for each year.
The plats receiving a particular fertilizer are likewise compared with the contiguous nothing flats for each year, and the average gain is noted for each group.
TABLE No. 10. Experiments in Field No. 6. Results in groups of Plats treated alike for each Year of the
Average of 8 plats of Berry's Bone Dust.
Average gain for Berry's Bone Dust...
IMPROVEMENTS IN TILE-LAYING.
BY M. MILES.
Thorough drainage is now so generally admitted to be of the first importance in the amelioration of soils, that any improvement of the processes of tilelaying cannot fail to be of interest.
In the construction of drains on the College farm for several years past the “boning rods,” described by most writers on drainage, have been entirely discarded, other methods of getting the grade having been found more convenient and satisfactory. In the use of the boning rods” two persons are required, the one holding the rod at the point where the grade is being made, and the other to sight over the rods placed at each end of the slope.
If several persons are employed on the line of the ditch the frequent "sighting" required on slight slopes interferes to a considerable extent with the work.
Where the tiles are laid in quicksand or in soft peaty soils, as is often the case, the “boning rods" are far from being a satisfactory means of determining the grade.
A line drawn above the middle of the ditch, from which measurements may be made, as recommended by some writers, furnisbes a better means of determining the grade in cases where great accuracy is required, or where from the presence of quicksand the ditch cannot be kept open for but a short distance beyond where the tiles are being laid.
In many places on the College farm good work could not readily be done without the line as a basis from which to measure the depth of the ditch and the ouly objection to it in practice was found to be the difficulty of adjusting it accurately and keeping it in place.
This objection was, however, obriated by the following device, which has proved 80 satisfactory in an experience of several years that it is now thought to be almost indispensable.
Two strips of pine board or other light wood, about 7 feet long and 24 to 3 inches wide, are joined by a small carriage bolt placed about 6
inches from the upper end, and forming shears, as Fig. 1.
represented in Fig. 1. The foot or lower end of these strips should be square so that they will not readily settle into the ground when pressed on from ubore.
Two of these shears are placed astride the ditch at a distance from each other of six to eight rods, or even more. They can be readily adjusted to the required height by spreading or contracting the legs, and at the same time the top is easily placed in position over the middle of the ditch.
The line, which should be small and strong like a mason's line, passing over the fork at the upper end of the shears, should be wound once around one of the short arms, to prevent slipping, and then fastened to a peg driven into the ground some six feet from the foot of the shears and nearly in the line of the ditch. If the peg is driven nearer the foot of the shears than the height of the line above the ground the strain will be greater on that part of the line between the top of the shears and the ground than it is between the two shears, and the line will be liable to be broken near the end wheu subjected to the necessary tension.
The smaller the line the better, if it has the required strength, as it is then 88 liable to sag between the shears.
To prevent the line from sagging when the shears are quite a distance apart, "guuge stakes” of the form represented in Fig. 2 are placed at convenient intervals along the ditch between the Bbears.
A round rod of hard wood, about seven feet long and one and one-half inches in diameter (a long fork handle will answer), forms the vertical part of the gauge. This rod should have a sbarp iron point at the lower end (which can readily be made from a piece of gas pipe), and an iron band at the upper end, to prevent splitting when driven into the ground. The horizontal arm, about two feet long, should be 2 by 2 inches, at the end throngh which the vertical rod passes, and tapering, for the sake of lightness, to of an inch square at the opposite end. A rivet should be put through the base of the arın back of the key, to prevent splitting. The vertical rod is driven into the ground Dear the edge of the ditch, and the horizontal arm is slid up Fig. 2. until the sag of the line is corrected, when it is secured by the key which clamps it to the rod.
Figure 3, showing the shears and gauge rod supporting the line in place over the ditch, will give a better idea of this device for getting the grade, than any description.
In laving tiles from three to four feet deep our practice has been to adjust the line seven feet above and parallel to the desired grade, and then to make use of a seven-foot measuring staff to determine the depth of excavation required below the line. If the ditches are deeper the line can be placed higher and a longer measuring staff used to correspond to the increased height. When working with a seven-foot staff if all but the last foot of the excavation is made before the line is put up, it will not be in the way, as it is bigh enough to allow a man to work under it when standing in the ditch.
In finishing the ditch the draining-scoop is one of the most important implements.
There are two forms of the draining scoop in common use, the “push scoop,” represented in Fig. 4, the “pull scoop,” represented in Fig. 5.
Persons not accustomed to the use of these forms
of the “scoop” will find them awkward impleFig. 4. ments to manage, the push scoop being heavy on Fig. 5. the point when loaded, and tending to roll in the hands, while the pull scoop trembles and springs when it meets with any obstruction.
From the position of the shank at the end of the blade both forms are liable to break if not used with great care.
An improved form, which we call the "College scoop," --represented in Fig. 6,-combines the advantages of both the “push" and "pull" scoops, while it is not open to the objections of either.
The position of the shank in the middle of the blade not only gives a balance to the implement that makes it easier to manage, but adds to its strength by diminishing the leverage between heel and point when the handle is depressed in working. The convenience of using the same implement in pulling or pushing, as the work may reqnire, is an important desideratum.
The handle of the scoop (not shown in the figures of full length), for deep work, is usually seven or eight feet long, and the blade for the purpose of jointing the bed for the tile is about 16 inches.
Where the line is used as described above for getting the grade, the blade of the scoop may be only ten to twelve inches in length, as the proper grade is then readily gauged at any point by measuring from the line, and the process of jointing is not of so great importance.
QUICKSAND. It seems to be generally admitted that tiles laid in quicksand Fig. 6.
should be placed on boards or some other firm substance, to prevent uneven settling and displacement of the tiles. This is a great mistake, and without doubt is the cause of failure in many cases. Collars placed over the joints of pipe are to be preferred when they can be obtained, but they are not indispensable even in the worst forms of quicksand.
On the College farm we seldom make a ditch of considerable length, four feet in depth, without striking quicksand to a greater or less extent, at some point on the line. We now have several hundred rods of tile drain laid in quicksand, that is working perfectly without any boards or eren collars to keep the tiles in position,-and it will be safe to say that there are but few places where the tiles vary over one half inch from a true grade.
Our practice is to begin at the outlet, and lay the tiles as fast as the excayation is made.
In four-foot drains the last foot is often quicksand, and in the deeper portions, when passing through a knoll at a uniform grade, it is sometimes two and one-balf feet in depth.
As soon as the quicksand is reached, the line is adjusted above the ditch, and a light, short-bandled scoop is used for making the excavation. The blade of the scrop should not exceed one foot in length, and the handle should be from four to five feet long.
In making the excavation, great care and judgment is required, and the work should be performed with as few motions as possible.
If the handle of the scoop is depressed when the blade is in the sand, the air cannot enter under the point of the scoop, and the quicksand will rise and fill the space under the point, so that the ditch will be as full as it was before the scoopful was taken out. If this process is continued, a cavity will be formed under the edge of the banks, and they will then cave in.
The proper method of excavating is to insert the scoop carefully into the quicksand, with a single slow motion, and then raise the heel so that the air can enter between the sole of the scoop and the sand.
The load is then raised vertically without any lateral motion of the hands, leaving a groove in the sand of the size and form of the scoop.
By a little motion of the foot or by laying the scoop on the surface of the sand and giving it a trembling motion so that a slight tremor of the quicksand is produced the sand will begin to run, and the groove before made will be obliterated.
Success in excavating will depend to a great extent upon avoiding any such exciting causes of disturbance while lifting the sand in the careful manner described above.
In measuring from the line to determine the grade the measuring staff shonld not be allowed to stand upon the bed already made or to be pressed upon it with any suddeu motion.
When the bed is prepared for two lengths of tile they shonld be laid at once with great care, and the joints protected with a thin firm sod.
They should be covered with soil from the surface that is not lumpy, and the ditch should be filled in to a point a little above the surface of the quicksand. This furnishes a firm platform for the workmen to stand on when making the next excavation and laying the next two or three tiles.
The filling in is a matter of great importance, as the sudden fall of a shovel of earth from the height of one foot or less will set the sand in motion and displace the tiles that bave been properly laid. If one side of the ditch is filled faster than the other, the same effect will take place. The only danger of displacement, in fact, arises from destroying the equilibrium of the sand, or in giving it vent so that it can run.
When the tiles are in place, and the filling in recommended has been done,