108 THE UNITED STATES GEOLOGICAL SURVEY [bttll.227. 
that the relative positions of the various details in the three colors are 
exactly as on the manuscript. Discrepancies are noted, and when 
satisfactory adjustment has been made the sheet is approved for 
printing. 
Section of Illustrations. 
Clear presentation of the subjects with which most scientific papers 
deal demands the use of illustrations, and many appear in the reports 
of the Survey. These illustrations are not selected for their pictorial 
value, but because they assist the reader to understand the text and 
the subject treated. In works on paleontology, for example, the need 
of illustrations is so great that it is necessary to figure each type, and 
often each species, in order to adequately describe its characteristics. 
For similar reasons the geologist illustrates his paper with structure 
sections, maps, and landscapes, in order that the reader may see, I 
almost as well as if he were on the spot, the phenomena under con- 
sideration. 
Prior to the beginning of the fiscal year 1884-85 no corps of artists 
or draftsmen was permanently emplo}^ed in the Surve}\ The illustra- 
tions were prepared, suitable processes of reproduction were selected, 
and proofs were examined by one of the geologists (who was also an 
artist of exceptional ability), either personally or under his direct 
supervision, or by contract with persons specially qualified. In a few 
instances the geologists and paleontologists made their own drawings. 
In a report to the Director dated July 13, 1885, the geologist in 
charge of illustrations stated: " During past years it has been the 
practice of the Survey to give out a large portion of the work of pre- 
paring illustrations to competent draftsmen not connected with the 
office. This method seemed to be open to objection, and, acting in 
accordance with instructions from you, I have, within the fiscal year, 
selected a number of draftsmen having especial qualifications for the 
work who have been regularly attached to the Survey. The results 
appear to be entirely satisfactory." This report led to the organiza- 
tion in 1885 of the section of illustrations. 
At this time there were four draftsmen, including the chief, regu- 
larly employed. Other draftsmen were temporarily engaged under 
the direction of the persons for whom the drawings were made. The 
number of draftsmen now regularly employed is ten, including the 
chief. When there is exceptional demand, work is occasionally given 
out to draftsmen not connected with the Survey. 
The section of illustrations and the section of texts necessarily coop- j 
erate during the preparation of the manuscript and the illustrations 
for a paper, in order to adjust the two parts. The originals from which 
illustrations are to be prepared generally consist of material of one 
or more of the following classes: Diagrammatic drawings (sections, j 
