The daily morning journal and courier., 1897-12-22

paint" said Engineer North, yesterday, but when we got ready to do this work and advertised for paints I was talked deaf, dumb and nearly blind by paint men, until I had to throw up my hands, We determined then to give everybody q chance to prove what he said"
 The result was that a very interest ing experiment was begun. Seventeen different paint-making houses, all of high reputation were selected, and each one had space assigned to 1t, upon which it's paint is to be tested. Some of the firms will put on two or more kinds of paint. There are oxide paints, sub oxide paints, varnishes, and plain paints of white lead, red lead or zinc. When these paints have been in use year it is believed that the result will be of great value to engineers as guide for further experiments. Some are cheap and others cost eight times as much.
 The section of the viaduct which was rusted included seventeen bents, and was about one hundred and seventy five feet in length. Each bent is sup ported by a lattice truss seventy three feet long and nine feet deep. Over lIIGoS llusSC diS St6Gl Soll bCI eRAiei sAtSSS in turn support steel plates on which the stone pavement of the roadway and the asphalt of the sidewalks are laid. It was found that the rust had not at tackled the riveted work and it was not necessary to replace any of the steel. Much difference was found in the cut ting power of different sands. Ordina- " building sand was first tried. Then sand was brought from Huntington Harbor, Long Island which was dug in twenty feet of water. This was washed free from salt and screened until it would go through the meshes of one- tenth inch, but not through others of fifty to the inch. When this had been used it was swept up and used again until it had been through the nozzle | three times. By that time it was as fine as flour, and was thrown away. It took about one- third of cubic foot of sand | each time to clean a square foot of steel 1 surface, and the work cost at first as much as twenty cents a foot. Later this cost was reduced to about six cents. This was after the men had gained eX- | perience and new sand was put into use. This sand is a by-product of Edi- sons latest project, the ogden mine iron works. It consists of the sharp parti- c1es of the crushed Jersey rocks, out of which Edison has drawn all the iron ore This sa d is in demand for build ing purposes also.
 The work on the viaduct is nearly done and in few days the scaffolding will be removed. The trouble from leakage, which led to the examination of the viaduct, was caused by loosen- ing of some of the sidewalk and pave ment through the unequal expansion of the steel, the stone and asphalr, and some right-angled bends in the pipes which led the rain water off from the viaGcct gutters. These bends got stopped up at times, and the back water ran down between the pavements and the steel work All these defects have been repaired and pipes without bends are to be put in.
 One of the curious things about the action of the sand blast is the way it destroys the chilled cast iron noZzles. In two hours the hole in nozzle is en- larged from nine. sixteenth inch to three-fourth inch, and in a few hours more hole is form completely through the side of the nozzle. These holes are oblong and always of the same shape, and no one knows why they are pre- duced in that form.