The publication of new work depends upon a variety of circumstances. The publisher pays either in cash or in royalty, or both, according to the prospects of sale. In case of authors of reputation this prospect can be reasonably well gauged. In case of unknown authors the publisher must take a risk if he buys a manuscript. In many cases the publisher will require a guarantee against loss on an edition of a certain size. He may require this guarantee because he has doubts about the success of the work or because it is a book of such limited circulation, although it may be of the most important character, that the publication will not be commercially profitable. Of course, if an author is determined to see himself in print and no publisher will take his work on any terms, he can hire a printer to make up an edition, can get it copyrighted, and can dispose of it in such way as he may find possible or desirable. From this legislation really dates the differentiation of the trade. This was a matter of economic growth rather than of legislation. The author might print and publish and sell his work, the printer might publish and sell, the bookseller might print and publish, but in either case there was an added risk combined with a possibility of greater profit. Most persons are content with smaller profits, providing they can be released from risk. Under the system which now developed the publisher assumed the risk. In that way he became the patron of both author and printer. The first of the modern type of publishers was Jacob Tonson, the elder, who began business in 1678. A consideration of the development of the publishing industry would take us too far afield and it will be touched upon only as it directly concerns the development of printing.