This article is the best explanation for the very limited success of typesetting machines up to 1871 that I have seen in the literature of the period. Whether any actual examples of the Alden machine illustrated have actually survived may not be known. The machine appears to be more compact than others, and unlike most machines it seems not to have used gravity to feed the metal type. According to p. 480 (which follows) the machine "has been in practical use, by Messrs. Appleton, the New York publishers, on book-work, for several years."