The evils of ill-fitting shoes are corns, bunions, and calluses.
Corns are mainly due to pressure and friction. When the layers of skin become hardened, they form a corn, which is merely a growth of dead skin that has become hard in the center. This hardened spot acts like a foreign body to the inflamed parts.
A hard corn is formed more by friction than pressure. It is produced by the constant rubbing of a tight or small shoe against the projecting parts of some prominent bony part, as the last joints on the third, fourth, and little toe. When this action continues, it produces inflammation. Rest—as relieving the feet of the friction—decreases this inflammation, leaving a layer of hardened flesh. Renewed action reproduces the same effects, leaving behind a second layer of hardened flesh. This continued action and reaction brings on a callus, rising above the surface of the skin. This increases from its base. An ordinary hard corn may be removed by scraping up the callous skin around its border, and prying out carefully with a knife. Soft corns are chiefly the result of pressure or friction. These corns are soft and spongy elevations on the parts of the skin subjected to pressure. Soft corns are mostly found on the inner side of the smaller toes. Those on the surface of joints by mechanical action will become hard.
The blood corn is excessively painful. It is the result of an ordinary corn forcibly displacing the blood vessels surrounding it, and causing them to rest upon its surface.
The bunion is an inflammatory swelling generally to be found on the big toe joint. The chief cause of bunions is known to be the wearing of boots or shoes of insufficient length. The foot, meeting with resistance in front and behind, is robbed of its natural actions, the result being that the big toe is forced upward, and subjected to continuous friction and pressure. The wearing of narrow-toe boots that prevent the outward expansion of the toe is another cause.
The comparisons of quantities are often called ratios. The ratios of the different parts of the foot to the height are different in the infant from that of the adult period. Between these two periods the ratios are constantly changing.
There are two series of shoe sizes on the market; the smallest size of shoe for infants (size No. 1) is, or was originally, four inches long; each added full size indicates an increase in length of one third of an inch (sizes 1 to 5). Children’s sizes run in two series, 5 to 8, and 8 to 11; then they branch out into youths’ and misses’; both running 11½, 12, 12½, 13, 13½ and back again to 1, 1½, 2, etc., in a series of sizes that run up into men’s and women’s. Boys’ shoes run from 2½ to 5½; men’s from 6 to 11 in regular runs. Larger sizes usually are made upon special orders. Some few manufacturers go to 12. Women’s sizes run from 2½ to 9. Some manufacturers do not go above size 8. The rate of sizes is sometimes varied from by manufacturers of special lines of shoes. A man’s No. 8 shoe would be nearly eleven inches long. These measurements originated in England and are not now absolute.
A system of French sizes is used which consists of a cipher system of markings to indicate the sizes as well as widths so that the real size may not be known to the customer.
All feet are not alike in structure and shape. In infancy the foot is broad at the toes, which press forward in the direction of their length. The heel is small in comparison to the width of the toes, and also short in length, due to the undeveloped bones. But during growth, the thickness above the heel bones disappears, and the heel itself becomes thicker and assumes the beauty of perfection at maturity. This development is due to the growth of bones which must be well exercised and properly cared for during this period. The various parts of the feet and legs do not mature at the same rate—those at the upper part of the body increase at a greater rate than the lower parts. Thighs develop first, next the upper part of the legs, and lastly the feet.