DELMAR K. MYERS The Pennsylvania State College Center, Harrisburg, Pennsylvania
THE
use of objects, specimens, and models as teaching devices is a most effectivemeans of showing the connection of a particular subject-matter field with its practical application to industry and business. The field of chemistry abounds with materials that can he used to enrich the texts and reference hooks that are normally used in chemistry courses. The return of a competitive market, together with the normal cooperation that educational institutions receive from business and industry, presents an excellent opportunity to begin such a project. The teaching device which is to he descrihed resulted from the writer's desire to make use of a highly heterogeneous collection of unused commercial exhibits that greeted him upon his arrival a t a new teaching situation. I t is not always possible to ohtain sufficient space in the usual high school or junior college to set up a permanent display of a great number of these aids. Perhaps this is for the best, as the exhibit is soon taken for granted and is seldom observed when the novelty has worn off. All of the advantages of a scientific museum, plus some additional benefits can be secured from the device presented. A table 26 in. wide by 48 in. long and 36 in. high was secured. A 4I/2-in. piece of in. plywood was attached vertically to the front edge; a similar piece 11 in. high was placed along the hack edge. On each end was placed a piece that can best he constructed by referring to the figure. A piece of shelving 8 in. wide was attached to the top of the hack piece. By means of suitable support, a piece of double-strength window glass was placed on the sloping opening. This highly sat.isfactory construction may be changed to meet the
local situation. I n any event, the cost is extremely small for the benefit derived. Breakage caused by students leaning on the glass was not a prohlem. A humorous sign "KEEP OFF THE GLASS" printed on a large gummed sticker solved the prohlem. Each week a different display was placed in the case. As far as possible the displays were related to the topic that was discussed in chemistry classes during that week. For example, the text discussion of elements and compounds coincided with a display of materials used in the manufacture of the telephone. These included iron, tin, copper, zinc, beeswax, wool, phenol resin, cotton, talc, coal, and some 20 others. When chlorine was the classroom topic, an exhibit of chemicals ohtained from sea water was used for the weekly display. The chapter on the metric system was made more meaningful when, with the help of a local pharmacist, various graduates, beakers, pipets, and other laboratory equipment, which included a set of metric weights were displayed. While the metals were being studied, several fine exhibits that dealt with specific metals and their alloys were shown. In some cases, the commercial exhibits were supplemented with local purchases. For example, two fusible alloy sprinkler valves were obtained for inclusion in an exhibit of bismuth and its compounds. Frequently, without resorting to any supplementary materials, the entire exhibit was secured from the chemistry stockroom. The source of the original exhibit materials is not known, but the writer had no difficulty increasing the number of exhibits. Letters addressed to chemical companies usually brought materials that could he used, or pamphlets which were placed in the library for reference. Three of the finest displays were obtained by interested students who brought: a collection of tanning chemicals and 20 grades of hished leather; samples of the materials used in the making of paper, complete from chips to printed pages; substances used a t a local plant in the manufacture of pottery and vitrified china. It should not prove difficult for an instructor to secure materials for display. In order to ohtain additional materials a joint project was sponsored in cooperation with the English Department. Each student selected or was assigned by the chemistry instructor a company to which he wrote. After proper clearance, to avoid duplication, a letter which descrihed briefly the project and requested assistance was written. This letter was checked and graded by the English instmetor; later, a letter of acknowledgment wa. sent to all responding
NOVEMBER, 1949
611
companies. Where the letters could not he addressed such a venture. Student participation in such a projto an individual, the request was sent to the sales ect would reduce the instructor's duties to supervision manager. In one case, the reply included 14 photo- of the construction of the display case and to supergraphs, product samples, and reference material. vision of the requests that are to be sent. The eduWith much of the present academic year still ahead, cational value of such a display is great in terms of the it u~ouldseem to be a most appropriate t.ime to begin knowledge obtained and student interest created.
