of the adjustable die-stocks, but is rarely used. Pipes, especially the larger sizes, are sometimes cut by expert workmen with diamond-pointed or cape chisels, but this process requires too much time to be applicable to small pipes. The hack-saw is coming into use to some extent for cutting pipes, and is an excellent instrument for this purpose, as it does not tend to burr or crush the pipe, and is quite as rapid as the wheel-cutter. The dies for threading the pipes are of a solid form, each die fitting into a stock or holder with handles, or of an adjustable form, the dies being made of chasers, which are held where wanted and can be set in various positions by a cam. The adjustable dies can be run over the pipes several times, and hence work easier than solid ones; but in their use great care should be taken that the exterior diameter of the pipe is not made less than the standard size. The cutting edges of the dies should be kept very sharp and clean, otherwise perfect threads cannot be cut. In the use of the dies some lubricant, as oil or grease, kept on the iron will be found to add materially to the ease with which the work can be done, and will tend to prevent heating and crumbling of the pipe and injury to the threads. Taps are required for cutting threads in openings or couplings into which pipes must be screwed-an operation which the pipe-fitter seldom has to perform, unless a thread has been injured. The vises for holding the pipe should be such as will prevent it from turning without crushing it under any circumstances. Adjustable vises with triangular-shaped jaws on which teeth are cut are usually employed. In the erection of pipe great care should be taken to preserve the proper pitch and alignment, and the pipes should, to appear well, be screwed together until no threads are in sight. Every joint should be screwed six to eight complete turns for the smaller sizes, 2" and under, and eight to twelve turns for the larger sizes, otherwise there will be danger of leakage. It is a good plan to test the threads on all pipes before erection by unscrewing the coupling and screwing it back with the ends reversed. It is also advisable to look through each length of pipe and see if it is clear before erect ing in place; serious trouble has been caused by dirt or waste in pipes, which would have been removed had this precaution been taken. In screwing pipes together, red or white lead is often used; the writer believes this practice to be generally objectionable, and to be of no especial benefit in preventing leaks. The lead acts as a lubricant, and consequently aids by reducing the force required to turn the pipe. It will generally be found, however, that linseed or some good lubricating oil will be equally valuable in that respect, and will have the advantage of not discoloring the work. If possible, arrange the work so that it can "be made up with right and left elbows, or right and left couplings. Packed joints, especially unions, are objectionable, and likely to leak after use. Flange-unions, packed with copper gaskets, should be used on heavy work. Good workmanship in pipe-fitting is shown by the perfection with which small details are executed, and it should be remembered that bad workmanship in any of the particulars mentioned may defeat the perfect operation of the best-designed plant. APPENDIX CONTAINING REFERENCES AND TABLES. LITERATURE AND REFERENCES. The literature devoted to the subject of warming and ventilation is quite extensive, dating back to a treatise on the economy of fuel and management of heat by Buchanan in 1815. A most excellent compilation of this literature was made by Hugh J. Barron of New York, in a paper presented to the American Society of Heating and Ventilating Engineers at its first meeting in January, 1895, from which the following list of books has been copied : A Treatise on the Economy of Fuel and Management of Heat. Robertson Buchanan, C. E. Glasgow, 1815. Conducting of Air by Forced Ventilation. Marquis de Chabannes. London, 1818. The Principles of Warming and Ventilating Public Buildings, Dwelling-houses, etc. Thos. Tredgold, C. E. London, 1824. Warming, Ventilation, and Sound. W. S. Inman. London, 1836. The Principles of Warming and Ventilating, by Thos. Tredgold, with an appendix. T. Bramah, C.E. London, 1836. Heating by the Perkins System. C. J. Richardson. London, 1840. Illustrations of the Theory and Practice of Ventilation, with Remarks on Warming. David Boswell Reid, M.D. London, 1844. A Practical Treatise on Warming by Hot Water. Chas. Hood, F.R.S. London, 1844. History and Art of Warming and Ventilating. Walter Bernan, C.E. London, 1845. Warming and Ventilation. Chas. Tomlinson. London, 1844. Practical Treatise on Ventilation. Morrill Wyman. Boston, 1846. Traité de la Chaleur. E. Péclet. Paris. First edition, 1848; second edition, 3 vols, 1859. Practical Method of Ventilating Buildings, with an appendix on Heating by Steam and Water. Dr. Luther V. Bell. Boston, 1848. Warming and Ventilation. Chas. Tomlinson. London, 1850. Practical Ventilation. Robert Scott Burns. Edinburgh, 1850. Ventilation and Warming. Henry Ruttan. New York, 1862. A Treatise on Ventilation. Robert Richey. London, 1862. American edition of Dr. Reid's Ventilation as Applied to American Houses, edited by Dr. Harris. New York, 1864. A Treatise on Ventilation. Lewis W. Leeds. Philadelphia, 1868; New York, 1871. Observations on the Construction of Healthy Dwellings. Capt. Douglas Galton. Oxford, 1875. Practical Ventilating and Warming. Jos. Constantine. London, 1875. Warming and Ventilation. Chas. Tomlinson. London, 1876. Sixth edition. Mechanics of Ventilating. Geo. W. Rafter, C.E. New York, 1878. Ventilation. H. A. Gouge. New York, 1881. Ventilation. R. S. Burns. Edinburgh, 1882. American Practice in Warming Buildings by Steam. Robert Briggs. Edited by A. R. Wolf, with additions. New York, 1882. Steam-heating for Buildings. W. J. Baldwin. New York, 1883. Thirteenth edition published in 1893. The Principles of Ventilation and Heating. John S. Billings, M.D. New York, 1884. Heating by Hot Water. Walter Jones. London, 1884. A Manual of Heating and Ventilation. F. Schuman. New York, 1886. Ventilation. W. Butler. Edited by Greenleaf. New York, 1888. Steam-heating Problems from the Sanitary Engineer. New York, 1888. Metal Worker Essays on House Heating. New York, 1890. Heat-Its Application to the Warming and Ventilation of Buildings. John H. Mills. Boston, 1890. Ventilation and Heating. T. Edwards. London, 1890. Ventilation-A Text-book to the Art of Ventilating Buildings. Wm. Paton Buchan. London, 1891. The Ventilating and Warming of School Buildings. Gilbert B. Morrison. New York, 1892. Hot-water Heating. Wm. J. Baldwin. New York, 1893. Ventilation and Heating. John S. Billings, M.D. New York, 1893. Warming by Hot Water, Chas. Hood, C.E. Edited by F. Dye. London, 1894. In addition to this list of books a large number of pamphlets have been printed containing valuable articles on special subjects. The scope of this work does not permit any |