44 ILLINOIS STATE ACADEMY OF SCIENCE 



is free to trace the chart in outline with pencil, and later 

 it can be finished with indelible inks or paints. The 

 advantage afforded by this procedure is that one can 

 easily and at a very small cost make whatever charts 

 he desires ; that is, a person can include in a series just 

 exactly what he thinks will illustrate the subject best. 



The practice at our institution at Lisle is as follows: 

 Dr. Jurica makes the selection, and he, himself, traces it 

 in outline with pencil and leaves the rest to be finished by 

 the students with colored waterproof ink, directing, of 

 course, the choice of colors and all detail work. The 

 cloth used, which has been found to be very satisfac- 

 tory, is known as "binders", Velum cle Lux, and can 

 be purchased in rolls of 40 yards, ranging in price from 

 17 to 35 cents per yard, depending upon market condi- 

 tions. It is cut easily into sheets of any size with a knife 

 or razor blade. Our practice is to tack the roll to a kit- 

 chen table and to cut along the edge, cutting up the whole 

 roll at one time into sheets of uniform size. After 

 finishing the chart in detail, it is then lettered and 

 bound in loose-leaf form in strong covers made of 

 beaver board and mounted on a tripod. If one desires, 

 the chart could also be put on rollers, but as a rule this 

 does not keep so well. Moreover, where a quantity is 

 made, the book form on a tripod has a decided advantage, 

 for the lecturer can turn readily from chart to chart as 

 necessity demands. 



A probable objection may be that it is difficult to find 

 students capable and willing to finish charts. This, how- 

 ever, presents no difficulty; for if the teacher is able, 

 there is no class, not even on the high school level, in 

 which a number of students could not be trained, and who 

 would not be willing to earn some pocket-money. Be- 

 sides, the students as a rule take pride in their finished 

 products, especially if the proper credit for whatever 

 they do is given them. 



The delineoscope in itself is not very expensive, if one 

 considers the time it saves in outlining or merely measur- 

 ing off the illustrations according to the rules of propor- 

 tions. With this machine charts have been outlined, 

 ranging in time from 17 minutes to an hour and a hajf, 



