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.
This may be done by means of several systems. Some of these are based upon average relations without giving directly the variations needed for the kind of pattern best adapted to the particular type of last. Others have some relation to certain data gathered from the foot's proportion.
Based upon the observations that when the foot is raised at the heel, the curve at the back, above the heel, becomes more acute (when related to a stationary line), the higher the elevation the more pronounced the curve. The curve at the throat becomes straightened as the heel is raised.
First, obtain a surface-area covering for the last for which the pattern is intended. Draw a horizontal line, AB (Fig. 110), and at the right-hand end, B, erect a perpendicular, BC. From B, in the direction of C, mark D, which is the height of the heel desired, or that for which the last is built, less the substance of the forepart of the former. The counter-height * will be measured from D to point E. Also from D is measured the ankle-height F. Find the centre between the counter point E and the ankle F, and name this Gr. Divide the distance between D and B into four equal parts, and from Gr, towards the toe portion of the pattern, measure off one-fourth of DB, and name this H. Above F mark K, which is also equal to one-fourth of DB. From F make a line parallel to AB and equal in length to one-half of the ankle-measure (FM, Fig. 110). Through M draw a line parallel to CB and at right angles to AB. This line will indicate the front of the standard. The forme is taken and put level with the base-line, and at the same time touching point D and the counter-height E. Trace the forme, add lasting-over allowance, and measure the height of top of leg of pattern required. The heel-measure line maybe drawn, and the average will be at 42° with the dotted line shown in the illustration. Complete the tracing, making suitable curves, and the standard will be ready for cutting out and will resemble Fig. 110.
* This may be obtained by taking one-quarter of the instep-girth of the last.
This is taken as one-half of the foot's length, and for a size 4's (say) would be 41/2 in.
The same method is adopted for constructing a men's standard, and is illustrated in Fig. 111, the counter-height E and ankle F being proportional to the size selected, and following the rule given for the ladies'. The marking of a golosh "to lock" is also exhibited on this diagram, the height of golosh being indicated at N. A straight line is drawn from N towards T, which represents the "crease"-line of the golosh or vamp. At right angles to the crease-line draw the dotted line NP, and divide into three equal parts RS. From W measure the distance PR towards X. Join XR and obtain range of golosh. The front curve may be made according to the style of toe of the last. A pieced-golosh may be made by drawing a line from the edges of forme, where the front line passes, so that it makes an angle of 90° with the range-line (Fig. 111).