It should be a matter of thankfulness to author and reader, or rather to both instructor and student, for this is designed to be an educational work, that the Laws of Nature are unchangeable.

From age to age and co-extensive with the globe the immutable principles underlying and actuating the physical states of all matter remain steadfast; gaseous bodies expand by unchanging laws which are obeyed down to the merest atom, fluids flow by law and the earth to the smallest particle remains firm, all things at all times responsive to the mandates of the Author of Creation.

The silent, mighty, unanswering physical characteristics of Gravity, Cohesion, Tenacity, furnish an agreeable contrast to the din, discord and frequent argument, to the verge of hatred, that have too often accompanied the efforts of mankind to co-operate with the forces of Nature. But now, between author and reader, let it be hoped, that in the unfolding of the subject-matter of this work that kind consideration will be extended and that some of that peacefulness and trust which existed on the earth, when flints were the weapons and the gourds the only goblets, may prevail from beginning to the “finis” of the volumes.

The author in planning the outlines of this work has aimed to keep close to real things belonging to the practical side of hydraulics, pumps, pumping-engines, and to the simple explanation of the Natural Laws pertaining to their industrial application. A knowledge of the real things in the objective world about us and the laws that govern them in their inter-relations is of practical value to every man; all branches of science are simply branches of one great science and all phases of human activity are touched by it; man is so constituted that he must have something to be interested in, and if he has no resources within himself he looks elsewhere, and often to his own disadvantage.

And so, the author has aimed to make the subjects of this book interesting as well as useful; 1, by their self-help arrangement; 2, by the illustrations, and 3, by leaving very much to the further research and investigation of the reader, as, in a well-told story, many things are left to the imagination of the listeners.

It should be borne in mind by the reader, that the work is designed to be seriously Educational in its plan and scope, and Progressive in the presentation of its subject-matter; nothing has been withheld that might add to its lasting value.

This is said in the way of an introduction to the Table of Contents to which the student is referred as showing the method of treatment, in the wide range of the theory and practice, of this important branch of Industrial Science.

In the back of the volume may be found a Ready Reference Index which by its admirable method of arrangement affords a speedy key to the contents of the book when occasion requires.

The well-known pump expert, Mr. F. Meriam Wheeler, writes us saying that if the manufacturers of steam pumps would send out with their pumps a card reading something like the following, it would probably impress the men who run the pumps more forcibly than anything that could be said or written in the ordinary way of giving instructions:

“Please do not gorge me with oil, as it will give my steam chest indigestion. What I like is a steady diet and thus enable my valves to work smoothly and with durability. A very small amount of oil fed to me steadily is the thing—it saves oil and repair bills.

“Two or three times a year give me a good dose of kerosene, to clean out any obstructions that may have accumulated in the passageways of my steam chest, or on the face or working parts of the valve and valve-seat, or on the chest piston.

“Do all you can to help me make a full length of stroke, as it means that I will use less steam and do better work. The adjustable collars on the valve rod will allow you to regulate the length of my stroke to a nicety.

“By allowing me to make short strokes, you prevent my steam piston from getting in its proper cushion, which it would do if it could complete its full stroke. My steam piston is supposed to run up to the end of the cylinder and pass across the exhaust port, cushioning on the confined steam between said port and the cylinder cover.

“The hand wheels on the side of my steam cylinder are for controlling the amount of this cushion. For slow speeds these cushion valves should be shut tight. When running at ordinary speed or a high rate of speed, these cushion valves should be slightly opened.

“Once in a while take a look at my water cylinder. See that the packing of the water piston is not set up so tight that it makes me grunt, producing unnecessary friction and wear. Or, perhaps the packing is too loose a fit, or is worn out and needs renewing.

“Please see that my water valves are seating properly, because if they are not tight I cannot pump as much water as I ought to do for a given speed. Sometimes the springs on the backs of my water valves need renewing or looking after.

“If you have not already provided a good suction air chamber for my water cylinder, you ought to do it, because it will prevent the water column in the suction pipe from slapping the face of my water piston at the end of each stroke in a harsh manner and so produce ‘water hammer.’ A good suction air chamber, properly located, saves wear and tear, and makes a pump quiet running.

“Please keep me nice and clean. I may not be of as much importance as your big engine, but there is no reason why I should not be kept free from dirt and grease. I hate to have oil slobbered all over my steam chest, or my stuffing-boxes left leaking.

“You will find it pays to keep me in good condition, like a well-groomed horse. Treat me well and I’ll serve you well and long!!!”—The Engineer.