The nature of the work of the Press itself — and this will apply, to a greater or less extent, to any similar in stitution affected by local conditions — constantly calls for modification, now of this rule, now of that. It would be found impracticable, even were it desirable, to bring all its publications into rigid uniformity of style and appearance. Methods have been devised, systems evolved, in certain lines of work, which cannot be carried bodily over into the field of others. Thus, in the matter of literary references, for instance, general practice has established certain usages in some of the sciences which it would not be advisable to ignore. Similar differences in practice may be observed in other directions. These deviations from the general rules will be found mentioned at the appropriate places in the body of the book. On the whole, however, the rules are designed to govern all publications sent forth with the official publishing imprint, The University of Chicago Press.