An electrotype of any cut on hand will be furnished for use in publications other than those of the Geological Survey at the cost of making, which is 3-1/2 to 5-1/2 cents a square inch of printing surface. The minimum charge for a single electrotype ranges from 46 to 60 cents. APPROVAL OF FINISHED ILLUSTRATIONS. After the drawings for a report have been prepared they will be submitted to the author or to the chief of his branch or division for examination. The finished drawings will be accompanied by the "originals," with which the author should carefully and thoroughly compare them. After making a thorough comparison he should mark lightly with a pencil, on the finished drawings, all necessary corrections, or indicate his approval subject to such corrections and additions as may be required. He should verify all type matter and other lettering and assure himself that no mistakes have been made in grouping the photographs into plates, especially such as have been regrouped since they left his hands. The author's list of illustrations will be submitted with the new drawings for this purpose. REVISION OF ILLUSTRATIONS. All illustrations receive editorial revision before they are sent to the engravers. After they are drawn they are examined with reference to their scientific features and their accuracy, and then in turn with reference to the correctness of geologic names and geographic names and to errors in statement and in spelling. Each illustration thus, before it is completed, receives critical examination by persons qualified in particular kinds of work to detect errors or omissions. SUBMITTAL OF PROOFS. The first proofs of all illustrations are submitted to an author when he is within reach, but if he is in the field and the transmittal of the proofs to him is likely to cause too much delay they are submitted to the chief of the branch or division in which the report was prepared. Second proofs of the more complicated illustrations, particularly geologic maps, may be submitted. An author's examination should be confined principally to the revision of the scientific features of his illustrations, but suggestions as to general effectiveness are always acceptable. The process to be used in engraving each illustration is stamped in its lower left corner. In examining proofs an author should note the following facts: 1. Changes can not be made in zinc etchings except by eliminating parts, cutting away defects, and connecting lines. If additions are required reengraving is generally necessary, and reengraving should preferably be avoided.