This question of economy will apply to the installation of a number of pumps driven by a number of engines, where the service varies at times; also to a series of tools or machines operated under varying demand at factories.

The Holly Water Works Co. carry out a combination of several steam engines operating one main shaft and make steam connection to their cylinders, so that some or all may be used for high pressure, or some as second expansion cylinders, as demand may require. This should meet the requirement of subdivision in installation for economical service very effectively.

In first installations frequently the engines are adopted largely in excess of present service required, as a provision for future extensions, whereby losses are caused in the meantime by increased frietion, by the necessity of carrying low steam pressure and by irregularity in motion due to injudicious expansion.

In transportation service the timely addition of the so-called hillhorse for vehicles and the pusher for railroad trains, at the steeper parts of the roads, is an established mode of working motors to nearest steady full capacity.

The auxiliary boilers and engines are found in large works for similar assistance.

From boiler tests on best constructed boilers it is to be assumed that the highest economy is reached by consuming 9 pounds of anthracite egg coal per hour per square foot of grate, producing 3, horsepower. This would give the ratio for best subdivision of boilers to suit a subdivision of engines in installation.

A NEW METHOD OF CASTING FLANGE PIPE.

BY

JOHN E. SWEET, SYRACUSE, NEW YORK.

EDISON says "he attributes a large part of his success as an inventor to the fact that he knows so many things that won't work" ; and again, that "he does not think he can make many more mistakes, as he must have made them about all already."

Our experience in attempting to cast flange pipe so they should come out of the sand complete has often reminded me of Edison's remarks, for I now know lots of things that won't work, while the number of mistakes appears to have reached about 95 out of a possible hundred.

Having too much foundry an order was accepted for a lot of flange pipe, and having too small facilities for facing and drilling the attempt was made to cast the ends faced true and the bolt holes cored.

The plan consists in casting the ends of the pipe against a chill, and the arrangement is shown in the figures. Fig. 1 shows the pattern, which differs from the ordinary pipe pattern in having movable flanges to suit different lengths of pipe, and in having the core prints the full size of the flanges instead of the size of the bore.

The flask, Fig. 2, is of the ordinary iron sort, having ends adjustable at intervals of a couple of inches, and with openings in the ends equal to the size of the core prints.

The core bar, Fig. 3, is an inch or two smaller than the pipe, having circular flanges an inch and a half or two inches apart and four ribs throughout its entire length.

The core bar has the ribs turned true and to a given size, upon which is fitted two chills shown as AA.

The chills may be set in any position to suit the length of pipe required. The faces are recessed so as to form a facing for the packing on the finished pipe; and as many holes as there are to be bolt-holes in the flange are bored completely through the chill, accurately spaced and reamed slightly tapering.

The outsides of the chills are turned to the same size as the prints on the pattern, except that there is left on the outside a small sharp

projection about 4 inch high—and this is the sharpest dodge in the whole scheme.

The chills when on the bar form journals, so that when rested in proper bearings the core bar may be rotated. Common moulding sand is used for the core, and when swept up is as true as if turned in a lathe. When the flask is rammed up and the pattern removed both ends are open to the full size of the flange. When the core is set the chills close up the ends except the holes for bolt cores, and the projecting V ribs are pressed into the sand and make a perfect stop to prevent the iron from running out.

Cores of the size of the bolt holes and some three or four inches in length are made and passed through the chills until they strike the green sand, so that when the pipes are cast the bolt holes are more nearly correct than the ordinary drilled holes.

For making the bolt hole cores we have blocks like the cylinder of a revolver, Fig. 4, with several holes in which the cores are made and baked, turning them out as perfect as if made by machinery. The faces of the pipe are smooth and good enough to pack with rubber gaskets.

This all seems simple enough now, but it worked with indifferent success until we learned the trade, and in learning the trade the apprentices made by far the best headway.