Fourth, speed of countershaft given, to find diameter of pulley for line shaft. Multiply number of revolutions per minute of the countershaft by the diameter of the pulley belting with the main line, and divide the product by the number of revolutions per minute of the line shaft.

ETCHING STEEL.

For etching names, dates, designs, etc., in steel, use any of the following recipes:

No. 1.-Iodine, 2 parts; potassium iodide, 5 parts; water, 40 parts.

No. 2.-Nitric acid, 60 parts; water, 120 parts; alcohol, 200 parts; copper nitrate, 8 parts.

No. 3.-Glacial acetic acid, 4 parts; nitric acid, 1 part; alcohol, 1 part.

BORING LONG CAST-IRON TUBES.

When boring long cast-iron tubes of large diameter-say 15 inches-excellent results may be attained by using kerosene as a lubricant, and a "packed bit" of the type used for gun-boring. Holes of the smoothness of glass will be the result.

TINNING CAST IRON.

The following tinning for cast iron will turn out whiter and harder than that with tin alone: Iron, 6 parts; tin, 85 grammes; nickel, 9 grammes. Dissolve the three metals in hydrochloric acid. This alloy will adhere well to the cast iron and present a very brilliant surface.

All tanks used for pickling cast iron in vitriol should be lined with lead and the seams burned together, not soldered. When a pickling tank is lined with zinc it will last but a short time under the action of the acid. Solder is also acted upon.

A HANDY DIE AND TOOL-MAKER'S CLAMP.

In Fig. 601 are shown sketches of a very handy clamp. It may be used for many purposes other than the one indicated. In this case it does away with the making of templets in die

making after the master blank has been made.

First, the exact centre of the die blank is found; then the blank is placed in its proper position on the face and clamped there as shown in the sketch. Then the outline of the blank is scribed.

The clamp may also be used to hold the steel block for the

DIE

BLANK

FIG. 601.

punch securely against the die face; thus facilitating the turning of the work to the light and examining the inside.

LUBRICANT FOR DRAWING SHELLS.

Attach

Take one pint of common lard oil, two pounds of opodeldoc soap, eight gallons of water; steam or heat until warm. a square pan to the front of the press and keep the shells well covered. With very small shells, such as primers or pencil tips, it will be necessary to keep the solution warm; but with large shells this will not be necessary. This is the best lubricant for drawing shells from thin metal that I have ever come across.

TO GLUE LEATHER TO IRON.

To glue leather to iron, paint the iron with some kind of lead color, say white lead and lamp-black. When dry, cover with a cement made as follows: Take the best glue procurable, soak it in cold water till soft, then dissolve in vinegar with a moderate heat, then add one-third of its bulk of white pine turpentine, thoroughly mix, and by means of vinegar make it the proper consistency to be spread with a brush. Apply the cement while

hot; draw the leather on or around quickly, and press tightly in place. In case of a pulley, draw the leather around tightly as possible, lay and clamp.

KEEPING NOTE-BOOKS.

Before concluding this chapter I feel that it will be well to present a few remarks on the advantage of keeping note-books in which to note and preserve the valuable and useful information which abounds in the mechanical press and which one becomes informed of through association with brother mechanics, or through experience and practical observation. It is a fact that the diffusion of knowledge is retarded greatly by mechanics in general trusting to their memory for the preservation of valuable information, instead of to more reliable means.

The most simple way to gain by one's reading and observation is to determine to fix upon some plan within one's capacity, means, and opportunity-those which come in one's daily routine -and to follow it preseveringly, regularly, and punctually, as an important factor in one's daily duties. Many men owe their success in life to the keeping of note-books in which they had noted information which, while of little moment at the time when written, proved of inestimable value at a later date.

A good way is to keep three note-books: one for jotting down items and notes and sketches which come to one in the shop through observation, hearsay, and experience. This book should be of pocket size. The second book should be a large, strongly bourd manuscript book having horizontal ruled lines. In this one can write something every evening-something one has read in a mechanical paper. The third book may be a scrap-book of the usual kind, in which sketches, small drawings, diagrams, and illustrations of new machines and appliances may be pasted. By following this suggested plan one will become a close and accurate observer, an enlightened and well-informed man, and a better mechanic; no matter what line he is engaged in, he will not only gain in knowledge, but may gain financially by publishing in the mechanical press any information which has come to him through experience and observation and which appears to be new or novel.

CHAPTER XXXIII.

The Value of Up-to-date Fixtures and Machine

Tools.-Conclusion.

IN the preceding chapters I have endeavored to illustrate and describe the most approved construction and methods for accomplishing the best results in modern tool-making and interchangeable manufacturing; and before drawing this work to a close I have thought it fitting to conclude by discussing the value of improved and labor-saving fixtures and machines, and to present what to me appears to be the only system by which the American machine-shop or manufacturing plant can retain its place at the head of the world's list of industrial supremes.

LACK OF KNOWLEDGE OF MACHINE TOOLS. Notwithstanding the vast amount of literature that is being circulated to-day describing and illustrating the uses of new machines, appliances, etc., for economic manufacturing, there is a woful lack of knowledge among shop managers, superintendents, and proprietors as to their possibilities, and among mechanics of how to operate them properly. If any one has an excuse for this lack of knowledge it is the mechanic; for while the heads of establishments are constantly receiving printed matter describing what the machine can do, and have representatives calling on them to discuss the labor-saving features of the machines they are selling, the mechanic has to rely solely upon the knowledge gained previously in the running of other similar machines to assist him in mastering the details in the operation of the new one.

"UP-TO-THE-MINUTE" MACHINE TOOLS

To-day the amount of money and time that is wasted every day in shops is apparent to very few. Even superintendents, shop managers, and master mechanics fail to realize the economy

that can be effected in the production of duplicate metal articles and interchangeable machine parts and the increasing of the efficiency of the output, by replacing worn-out and obsolete machines with others that are "up-to-the-minute," equipping them with suitable fixtures and tools, and operating them as they were designed and built to be operated.

ADVANTAGES GAINED THROUGH THE USE OF IMPROVED TOOLS.

It goes without saying that the most important item in the cost of running a modern machine shop or a manufacturing plant is the labor bill. The tools and machines in the hands of and operated by the workman determine the size of the output to a given size of labor account. Thus the advantages to be gained in manufacturing by the use of up-to-date machines and special tools and fixtures are obvious; as the cost of the machines and the amount expended in the designing and constructing of special tools will be quickly balanced on the profit side when the increased output and the efficiency of the parts produced through their use are compared with the results under the old methods. Another advantage to be gained through the use of improved tools is the almost total elimination of the obtainable results depending upon the degree of skill and intelligence possessed by the workman; thus allowing of employing less expensive help in the manufacture of the required parts.

The above enumerated advantages gained through the use of modern machines and tools should be so thoroughly recognized by the executive heads of manufacturing plants that the aim should be universal to weed out all inferior tools, and allow to remain nothing but the most efficient machines, tools, and fixtures in the hands of the workman; so that the mechanic may produce a greater quantity, or a better quality of work, irrespective of his degree of skill, and without increased exertion-mentally or physically.

IDEAL TWENTIETH-CENTURY MANUFACTURING.

Ideal twentieth-century manufacturing is attained through the constant endeavor of shop officials to increase the dividend