The average number of the eleven chief letters specified above would be about forty-four, while if we take into calculation the minor letters of the alphabet and the double letters, this average would be reduced to little more than ten. It will thus be seen that the founts of the earliest printers consisted of a small quantity each of a large variety of sorts. Mr. Astle, in his chapter on the Origin and Progress of Printing,[51] is, we believe, the only writer who has dwelt upon the difficulty which the first letter-founders would be likely to encounter in the arrangement of their “bill.” This venerable compilation was, he considers, made in the fifteenth century, probably by the ordinary method of casting-off copy. If so, it must have experienced considerable and frequent change during the time that the ligatures were falling into disuse, and until the printer’s alphabet had reduced itself to its present limits. * * * * * Of the face of type used by the earliest printers we shall have occasion to speak later on. Respecting the development of letter-founding as an industry, there is little that can be gathered in the history of the fifteenth century. At first the art of the inventor was a mystery divulged to none. But the sack of Mentz, in 1462, and the consequent dispersion of Gutenberg’s disciples, spread the secret broadcast over Europe. Italy, Switzerland, France, the Netherlands, Spain, England, in turn learned it, and after their fashion improved it. Italy, especially, guided by the master-hands of her early artists, brought it to rapid perfection. The migrations of Gutenberg’s types among the early presses of Bamberg, Eltville, and elsewhere, have led to the surmise that he may have sold matrices of his letter.[52] In 1468, Schoeffer put forward what may be considered the first advertisement in the annals of typography. “Every nation,” he says, in {29} the colophon to _Justinian’s Institutes_, “can now procure its own kind of letters, for he (_i.e._, Schoeffer himself) excels with all-prevailing pencil” (_i.e._, in designing and engraving all kinds of type).[53] For the most part printers were their own founders, and each printer had his own types. But type depôts and markets, and the wanderings of the itinerant typographers, as the demands of printing yearly increased, brought the founts of various presses and nations to various centres, and thus gave the first impulse to that gradual divorce between printing and typefounding which in the following century left the latter the distinct industry it still remains. * * * * *