This section is from the book "Spons' Mechanics' Own Book: A Manual For Handicraftsmen And Amateurs", by Edward Spon. Also available from Amazon: Spons' Mechanics' Own Book.
Hammers, with and without handles, are in use; hammers of various weights from 1/2 oz. to 10 lb., and from 15 lb. to 56 lb., are now employed as hand-hammers. The angles of attachment of handles to heads are various; the position of the centre of gravity of the head in reference to the line of penetration of the handle is various; the faces have various convexities; the panes have all ranges and forms, from the hemispherical end of the engineer's hammer, and the sharpened end of the pick and tomahawk, to the curved sharpened end of the adze, or the straight convex edge of the hatchet and axe; the panes make all angles with the plane in which the hammer moves. Various as are the uses to which hammers may be directed, yet like many other handicraft tools certain contrivances are requisite in order either to direct or give full effect to the tool itself. Art has given to the hammer head only the handle as its contribution. Nature supplies other and more essential contrivances. These contrivances are mainly the muscles of the arm, although under certain circumstances other muscles of the body, especially those about the loins, are called into action.
The weight of the hammer head, and the balance of the head in the handle, are the most important considerations governing the suitability of the hammer to the nature or the work as well as to the capacity of the workman. The ordinary ("Exeter") carpenter's hammer is shown in Fig. 403, consisting of a wooden handle fastened in an eye in the steel head by means of a wedge. Fig. 404 is the next common form, termed a " claw " hammer, and secured head to haft by means of side flanges. This is an inferior plan, as the elasticity of the blow is not only interfered with, but the head is liable to be loosened by using the claw for drawing nails. It is well to have 2 or 3 sizes for various work, costing 1s. to 3s. each. No hammer should ever be used to strike a wooden surface, especially an article lighter than the hammer itself, as it will certainly do mischief.