Foundation for Compound.

on iron wedges. When the frame of the engine is leveled and put into line, make a concrete of 1 part Portland, 21⁄2 parts sand and 5 of roofers' gravel or of small crushed. stone of the same size. Put just sufficient water in it so that when it is squeezed in the hand it would retain its shape. This is pushed under the machinery with a stick and rammed solid with an iron rammer. If too much water is put in it will not stay in place, but will fall away, so that care should be exercised that it is not too wet. This method takes longer than grouting and is harder work, but there is no doubt that it fits every place, that it is in solid, and makes a filling that is much harder and fits better than grout.

To prevent filling the holes around foundation bolts, fill the top of these holes with waste, excelsior or something similar.

The cut shows a foundation with base covering the entire ground under both foundations for a cross-compound engine. This is a good idea in any case, and especially so if the ground is not of good gravel. This plan shows pockets for getting at the bottom of the foundation bolts so arranged that access can be had from the wheel-pit side, allowing all around the outside to be filled if desirable and a cellar not wanted. The holes for bolts can be made by building in gas-pipe or boiler tubing or square boxes of wood.

Stakes have been used a great deal. They should be tapered, say from 4 inches at top to 2 inches at the bottom, and made smooth. They should be soaked in water for a week before using, so that they will not swell in the masonry. They should be pulled out as soon as possible after the foundation is finished. For this purpose, they should be sufficiently long to project 6 inches above the

Stone and Brick.

top of the foundation. A light chain should be put around the top and a lever of 4x4 timber, 12 feet long, with a good fulcrum, will usually start them. If not, have two or three men put a strain on the lever and hit the stake a good, square blow directly on top with a sledge and it will pop right out.

Foundations are built of brick, stone and concrete. An engineer was building some foundations, for an electric station, of stone according to the terms of the contract, when the civil engineer employed by the owners objected and wanted them built of brick. The M. E. asked for his reasons, and he stated that brick made a better foundation and that all foundations of that character in that vicinity were built of brick. The M. E. asked him what an engine foundation was for, and he replied that it was to hold an engine up. "No," said the M. E, "it's to hold an engine down and have it stay quiet, and to do this requires weight and stability, and stone fills the requirements better than brick, as it is heavier and stiffer."

To this the C. E. took exceptions, but after consulting his books admitted that stone had more weight, but would not agree with the M. E. that stone was stiffer and that brickwork would spring. "Well," said the M. E., "you go to any of the places where they have large engines on brick piers, and if you can find a single one where the engine is well loaded that it does not spring, I will take out the stone foundations and put in brick." The M. E. heard no more about foundations.

Good Portland concrete is getting to be universal for engine foundations, and is rapidly coming into use for making bridges, dams, and buildings. A concrete house costs about one-half as much as a brick one, and

Brick and Steel Chimneys.

the same is true of mills. It can be molded in any form and can be made to represent any kind of cut stone desired at a minimum cost.

Chimney.

When it comes to deciding on draft, and first cost has to be kept down, a steel stack is usually decided upon.

Carbonic acid and carbonic oxide gases are very destructive to steel, and a steel stack corrodes very quickly on the inside. The heavy, self-supporting stack will take longer to rust out than the thin, guyed ones, but they, too, must give way.

Fig. 42 is a brick chimney that costs no more than a self-supporting steel stack. It is very stiff and stands up against wind pressure in good shape. The inside shell. inches at the top. The outside shell

is 12 inches thick at the bottom and 8

It does not reach quite through the top. is 12 inches thick at the bottom and 8 inches during the latter part, except at the enlargement at the top. Commencing at the top, there are 18 inches for the bevel. This has a cast-iron cap with rabbeted joints, so that no water can get under the plate. Copper bolts, % inch diameter, are built into the chimney at the top, and when the cap is in place these are riveted. The cap reaches down 4 inches inside of the chimney and 4 inches over the base of the bevel. The square part is 12 inches and the slope is 9 feet. Below this, for 30 feet, the chimney is straight, and from that point to the bottom the batter is 2-10 of an inch per foot on each side. As shown on the plan at the base, buttresses are built into the outside shell and extend as high as possible. They should not come within 3

Reasons for Plain Designs.

inches of the inner shell at any point. Above and below the opening for the flue and at the top of the chimney there is a 22x2-inch iron band built in next to the outer course of brick, and every 10 feet there is a band, 11⁄2x inch, built in in the same way, so that the chimney is thoroughly banded, and yet they do not show.

The mortar should be made of one part lime to five parts clean, sharp sand, and when used one part Portland cement to one part lime should be added. When added the cement should be mixed with water before putting it into the mortar, otherwise the cement will be mixed in dry lumps. No more should be mixed than can be used within three hours of the mixing.

The outer course should be laid in what is known as "push joints," viz., the mortar should be put on the laid brick sufficient to fill the joint full, the brick laid in it and pushed to place. This fills the joint completely full. Masons object to this because it makes a little thicker joint. They like to stick a little mortar on the inside corner of the brick and lay it down as in an ordinary straight wall. This makes a very thin joint at the outside, with often no mortar for an inch or two, and a weak construction. All interstices should be well filled with mortar for strength and for tightness.

It will be noticed there are no rings at the top for looks nor any projections. All projections catch snow, ice and rain, and as water is a universal solvent, where there are projections there will be disintegrations.

There should be a ladder built on the outside of the chimney of 8-inch round iron, the steps being 14 inches. apart, 14 inches wide and projecting 9 inches, so that a man can put his leg through to rest. A chimney built as above, 6 feet internal diameter and 125 feet high, cost