The transverse portion at the back, termed the 'bar,' and which gives the shoe its name, is instrumental in bringing about from below that counter-pressure on the frog that we now know to be so necessary a factor in remedying contraction. When the frog, by wasting or disease, is so deficient as to be unable to reach the 'bar,' this shoe must be supplemented by a leather or rubber sole. In the event of corn or sand-crack existing with the contraction, the shoe known as a 'three-quarter bar' is preferable (see Fig. 103). The break here made in the contour of the shoe allows of dressing the corn, and, in the case of sand-crack, removes the bearing from that portion of the wall. _(d) By the Use of a Bar Pad and a Heelless or 'Half' Shoe_.--The bar pad consists of a shape of rubber composition firmly fixed to a leather foundation, which shape of rubber takes the place of the 'bar' of the bar shoe. [Illustration: FIG. 69.--RUBBER BAR PAD ON LEATHER.] [Illustration: FIG. 70.--THE BAR, PAD APPLIED WITH A HALF-SHOE.] For habitual use in such cases as prove obstinate to treatment, or where a complete cure was never from the commencement expected, the bar pad is undoubtedly one of the most useful inventions to our hand. The animal's 'going' is improved, the tender frog is protected from injury by loose stones, and greater comfort given to both the horse and the driver. [Illustration: FIG. 71.--FROG PAD.] [Illustration: FIG. 72.--FROG PAD APPLIED.] _(e) By the Use of a Frog Pad and a Shoe of Ordinary Shape_.--The shape of rubber on this pad is designed to cover the frog only. Its shape and mode of application is sufficiently shown in the accompanying illustrations. _(f) By turning out to Grass_.--Where the expense of keep is no object, a return of contracted feet to the normal may be brought about by removing the shoes and turning the animal out to pasture, thus giving the feet the advantages to be derived from a more or less continuous operation of the normal movements of expansion and contraction. In this case the treatment must extend from three to four, or possibly six months. 2. _By the Use of Some Form of Expansion Shoe_. [Illustration: FIG. 73.--SMITH'S EXPANSION SHOE SEEN FROM ITS GROUND SURFACE AND FROM THE SIDE. _a_, The screw, with a fine-cut thread; _b_, nut which travels along it; _c_, a hollow thimble into which the screw passes at one end, the other being cut out V-shaped to catch into a slot (_d_) on the shoe; _e, e_, the grip[A] for the bars, the length and direction of which depend upon the shape of the foot; _f, f_, the counter-sunk rivets forming the hinge (_f_'); _g_, the counter-sunk rivet of the expanding piece.] [Footnote A: The inventor of this shoe uses the word 'grip' to denote what, in describing other expansion shoes, we term the 'clip' (H.C.R.).]