This section is from the book "The Manufacture Of Boots And Shoes: Being A Modern Treatise Of All The Processes Of Making And Manufacturing Footgear", by F. Y. Golding. Also available from Amazon: The Manufacture Of Boots And Shoes.
* Paper scales printed on good Manilla paper are desirable, and, being cheap, may be renewed often.
Feet that may be alike in length and girth are different in many other respects. Some are arched, for instance, and some flat, and these things must be noted by the measurer. Any part out of proportion with the rest of the foot should be recorded. A difference between the feet of a single individual is quite common, and a measurement of both feet should be made in such cases.
The weight, age, and occupation must have consideration. The weight of a person will affect the "allowances" made in the selection or "fitting up " of the last, as the feet of a heavy person will expand more in walking than one whose body is lighter. The age, whether growing or mature, requires attention; as feet that are developing should have all allowances made to permit their growth, without cramping. If the occupation of the person measured involves carrying heavy weights, it should be taken into account when measuring, because when extra weight has to be transmitted to the foot, it expands to a greater degree, and should be treated as a foot of a heavy person.
A bony or a fleshy foot will require different treatment, and the measurer, who usually alone sees the foot, should make the allowances - or at least notify the conditions upon which they may be made. It is preferable, however, to give to the maker the net measurements.
A Draft or Plan of the foot must be taken, upon which the position or location of the points measured must be indicated. If properly taken it should afford the maker an idea of the arch of the foot, the relative position of the inside and outside joints; whether tapering or square toes ; and if corns, bunions, or other malformation be present, the exact situation can be indicated on the draft or plan.
To take the draft, a sheet of paper of suitable size should be placed upon a flat surface, such as the floor, and the foot, with the weight of the body of the person about to be measured, placed on the paper. A thin or split lead pencil* held vertically is carried round quite close to the edge of the foot. To indicate the arch the pencil is slanted as far under as convenient, and the waist marked. Any special prominence should be indicated, and pencil marks such as AA, BB' (Fig. 49), be made to locate the position of joints, instep, etc. Unless this is done, the plan loses the major portion of its usefulness. To ensure the lead pencil being held uprightly when tracing the outline of the foot, a simple piece of apparatus, as shown in Fig. 50, may be used, where A is a section of two triangular-shaped pieces of wood fastened together at right angles. On the face, B, of the larger piece of wood, is affixed two metal grooves to permit a lead pencil to pass to the corner of the apparatus. The edge of the wood that adjoins the point of the pencil is placed near the edge of the foot, and as it is carried round the outline is traced perpendicularly to the margin. A separate pencil is used for the waist. * A pencil that is used for compasses answers well for this purpose.
It will be observed that in addition to the outline on Fig. 49 there is an impression of the foot, which, if taken, shows the character of the sole and the parts of the foot that give the greatest pressure to the ground.
Foot-Impressions are specially useful when investigating the differences and variations of the sole-area of the foot. They may be produced in several ways. A sheet may be prepared that will do for many impressions on the plan of carbon tracing-paper ; or two sheets may be used, chemically prepared so that their positions of close contact will give dark impressions, by the chemical combination of two elements that give a distinct colour.
To produce the first kind, take a sheet, or sheets, of white filtering-paper (or any paper that is not glazed or sized), and soak it in a solution made by dissolving aniline dye in spirits of wine, and then adding about an equal quantity of glycerine. After draining and drying it may be used by placing it between some clean filter-paper and the foot placed on the top. This will give two good impressions reversed, one of which may be kept for reference and the other sent to the maker.
The second kind of impression-paper may be made by soaking white filter-paper in a strong solution of tannic acid and allowing to nearly dry. Another sheet must be soaked in a strong solution of chloride of iron and likewise allowed to dry. When using these sheets they are to be faced and the foot placed on the top, when, if the sheets are damp or moisb, a clear impression will result. A plan or draft tracing should be made at the same time (Fig. 49).
An Impression-Box may be made that will be more permanent than the paper transfers, and is used abroad for taking foot-impressions. It consists of a frame made of suitable size, upon which is stretched a thin sheet of indiarubber. This membrane is evenly coated with an aniline dye * when used. The frame is hinged to a box upon which is laid a sheet of white paper to take the impression. The sheet in place, the frame is lowered - the inked side of the rubber being in contact with the paper - and the foot placed on the upper surface of the membrane. When the frame is removed an impression of the sole-area of the foot is found.
* Judson's dyes answer well for this purpose.
The Measures that should be taken are length, girth of joints, instep, heel, ankle, and leg, with the height of ankle and leg from the ground. For long work these (excepting the ankle) and other measurements are required, such as calf, knee; height of calf, knee, etc.
The joint-girth is taken round the foot either straight across from the inside joints, or diagonally over the inside and outside joints. If the latter be adopted, their positions must be indicated on the draft. The instep-measure is taken round the foot over the top of the instep and under the centre of the foot's arch (Fig. 51,1). The heel-measurement is taken round the extreme backward point of the heel, across the throat or bend of the foot. It should not be taken up the leg, but as nearly as possible over the annular ligament (Fig. 21, AL, and Fig. 51, H). The ankle-measure is taken at the smallest part of the leg above the "ankle" bones. The leg-measure is taken at the extreme height required, and its height noted from the ground. The calf-girth is taken round the leg at its greatest breadth, and is usually situated from the ground the distance equal to the heel-girth. In any case it should be noted how far up it is taken.