With the tip the posterior half of the foot is allowed to come into contact with the ground, and the object we are striving for--namely, frog pressure, and greater facilities for alternate expansion and contraction of the heels--is thus brought about. [Illustration: FIG. 64.--THE TIP SHOE 'LET IN THE FOOT.] [Illustration: FIG. 65.--THE THINNED TIP.] _(b) By Shoeing with the Charlier_.--The results brought about by the use of a tip may be arrived at by the application of a Charlier or preplantar shoe, or by a modified Charlier or Charlier tip. Briefly described, a Charlier is a shoe that allows the sole and the frog to come to the ground exactly as in the unshod foot. This is accomplished by running a groove round the inferior edge of the hoof by removing a portion of the bearing edge of the wall with a specially devised drawing-knife. Into this groove is fitted a narrow and somewhat deep shoe, made, preferably, of a mixture of iron and steel, and forged in such a manner that its front or outer surface follows the outer slope of the wall. The Charlier should have the inner edge of its upper surface very slightly bevelled, in order to prevent any pressure on the sensitive sole, and should be provided with from four to six nail-holes. These latter should be small in size and conical in shape. The nails themselves should be small, and have a conical head and neck, to fit into the nail-hole of the shoe. [Illustration: FIG. 66.--THE SPECIAL DRAWING-KNIFE (FLEMING'S) FOR PREPARING THE FOOT FOR THE CHARLIER SHOE.] The modified Charlier, or Charlier tip, perhaps the better of the two for the purpose we are describing, is really a shortened Charlier, and bears the same relation to the Charlier proper as the tip does to the ordinary shoe. It is let into the solar surface of the foot in exactly the same manner as its larger fellow, but it does not extend backwards beyond the commencement of the quarters. By its use greater opportunity for expansion is given to the heels than is done by the Charlier with heels of full length. [Illustration: FIG. 67.--FOOT PREPARED FOR THE CHARLIER SHOE.] We do not here intend to deal at any length with the arguments for and against the Charlier as regards its adoption for general use. These will be found fully set out in any good work on shoeing. The point that it is correct in theory it would be idle to attempt to evade; but that it is generally practicable, or that it offers any very pronounced advantages, as compared with the disadvantages urged against it, over the shoes in ordinary use, the limited favour it has drawn to itself, since its introduction in 1865, seems sufficiently to deny. _(c) By the Use of a Bar Shoe_.--Where the frog is not excessively wasted benefit will be derived from the use of a bar shoe. [Illustration: FIG. 68.--BAR SHOE.]