A history of the evolution of the fric tion match would not be complete without some reference to the safety match, which is manufactured on a somewhat different principle. In this match the oxidizing agent, chlorate-of-potash, is separated from the inflammable portions of the composition, the former being on the head of the match, while the latter, con sisting chiefly of amorphous phosphorus, is affixed to the box side.
Since about 1900, the methods of match manufacture have undergone a complete change. From an industry in which practically every operation was conducted and completed by manual labour, it has become one of the most highly mechanized forms of industry. At the time of the introduction of Walker's Match, "Spunks" or splinters of wood were chopped off the wood-block in single units, and were dipped in the same man ner. This procedure has now given place to specialized machinery adapted to each and every stage of the manufacture. Modern matches are prepared from two species of wood: viz. :—American pine and aspen.
Probably the earliest effort to provide a speedier means of dipping the matches consisted in assembling the splints in serried rows in a frame, in which each unit was separated. After dipping the matches were then dried, assembled from the frame, and put into the boxes by female labour. The boxes were prepared by cutting a thin shaving from a piece of timber, previously sawn to the correct size and stamped by means of a die folding; then finally fastened down with flour paste, and paper.
In the modern match factory, ingenious mechanical devices are adapted to each process; in many instances the operations are combined on a single machine, notably on the so-called continuous match machine. There are two preparatory and essential requisites in the manufacture of matches, viz.:— (a) The preparation of the match splint. (b) The putting together of the boxes. In order to prepare the splint, a log with the bark still attached, about 8 ft. or more in length by about 1o" or more in diameter, is crosscut to obtain convenient lengths for sub sequent handling. A machine of a simple type is next brought into operation for the purpose of debarking the log. A vertically rotat ing disc, furnished on its face with several knives set slightly in advance, serves to expose the wood and leaves it free for further treatment, which consists in slitting the log into a thin veneer about
diameter. In this process in England the log is fixed between two dogs, or clutches, of the machine, which seize it at each end and hold it firmly enough to prevent its slip ping, while the shaving or veneer is being discharged. A revolving motion is then imparted to it, during which the log is incessantly pressed against a stationary knife. By this means the veneer is
formed in one long shaving, suitable for further treatment in a crosscutter, which descends upon the assembled veneer. The out put of this splint cutting contrivance approaches 2 millions per hour.
Impregnation of the splints in a chemical solution to prevent a glowing ember comes next, and for this purpose boric acid can be used. Splints are then dried and finally cleaned and straightened for presentation to the continuous match machine.
The making of the boxes follows up to a point the same route as the preparation of the splints, but with certain differences. The shaving is cut thinner, being only about i/3o* thick, and the veneering machine for this purpose is fitted with scoring knives, which serve to mark the shaving in the exact place for the convenience of subsequent folding. The assembled veneer is then submitted to the chopper and sliced into its necessary widths. A complete box is composed of three distinct pieces of wood: (a) The rim of the inside, (b) The bottom of the inside, (c) The outer case. There are two machines for the preparation of the box, the inner machine and the outer; both are automatic. A machine for making the outsides can turn out 8,000 to io,000 boxes per hour, while the inside machine can make 6,000 to 7,00o per hour.
On being assembled, the boxes are then carried forward to the continuous match machine. There are types, with varying capacity, but in round figures 7+ millions of matches can be paraffined, dipped, dried and put into their final resting-place in the space of 1 o hours by one of these wonderful machines, with the assistance of about four attendants. In area, one type occupies a space of about 53 ft. long by 10 ft. wide by 9 ft. high. It weighs over 20 tons. For the purpose of obtaining a good mental picture of one of these machines, an endless perforated steel plate of considerable length can be readily imagined, at the beginning of which the splints contained in a suitable hopper are inserted by a joggling mechanism and a plunger into the plate, are carried forward over and dipped into the heated paraffin, and thence forward to a container with the striking composition, where they receive the ignitive head. A further advance carries them over and under a series of planes, during which the drying is completed, which process occupies about one hour of time , until they arrive almost at the point from which they started, when they are ejected into the boxes, the inner of which has been previously placed into the outer by an apparatus specially designed for this purpose. The continuous machine then opens the empty box by a self-acting plunger, and closing it again in a similar manner, delivers it ready for the wrapping operation.