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For this reason the line-engraved steel-plate processis used almost exclusively by the Bureau of Engravingand Printing at Washington, D. C, and by a select groupof bank-note engravers who manufacture postage stampsand money for governments, and other securities wherethe utmost protection against counterfeiting is required.The number of expert engravers in the world is verysmall and their work is well known to all serious philate-lists as well as to all others in the trade. Once a steeldie has been cut, it is a permanent affair that, if keptcarefully, will outlast the ages. This method of printing finds very little use in com-mercial channels and when so used the printing is donefrom the original dies usually on copper. The authorknows of no instance where the multiple-subject platemethod developed by Perkins is used in ordinary com-mercial channels. . |
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