Research turns from paints to study the woods painted - American


Research turns from paints to study the woods painted - American...

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JOURNAL OF CHEMICAL EDUCATION

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JUNE, 1930

corrected and points awarded. After the four other contests in "equations and formula writing" have been staged, every one feels he has had a delightful and hilarious evening. After the program in the auditorium is finished, the patrons and students are shown through the laboratories, where the notebooks, essays, and displays that were entered in competition by the different schools are on exhibition; as well as notebooks, essays, displays, drawings, etc., of all the students of the home school. The latter include some work of other science classes as well as chemistry. Students are stationed by the displays and models to explain the different processes; students are also working a t the laboratory desks, doing some experiment that has a great community value. The system of scoring in determining the winner of the cup is very indefinite. It depends on teachers and schools, as does the entire plan above; i t must be changed to fit the school and locality. The usual method is, first place, five points; second place, three points; third place, one point; fourth and fifth places, one-half point. Following are the criteria by which the units are judged: notebookneatness, originality, order and utility; dis$lays-utility, time to prepare, chemistry involved, practicability and appearance. Essays-follow the rules of American Chemical Society. Equation and formula writing-see above. In conclusion we should add thabfull houses were present on each night of the competition; annual awards, for Qest displays, were offered to students by towns-people, hut more important is the fact that the pupils of the competing schools are actively engaged in a work that brings the interests and the thinking of the school and community closer together.

Research Turns from Paints to Study the Woods Painted. Not only the paint but also the surface have been receiving recently the attention of scientists. What qualities of wwd make i t almost impossible for paint to stick is revealed by Dr. F. L. Browne, senior chemist of the U. S. Forestry Products Laboratory a t Madison. Wis., in a recent report to the Engineering Foundation. "Paint fails by flaking from the summerwaad, the dense, horny, dark-colored part of the annual growth ring," Dr. Browne says. "As failure progresses the summemood may be left bare while the springwood is completely covered." Light-weight wood of even texture has thin bands of summerwood and holds paint well, he paints out. But most heavy wood is uneven with wide bands of summerwood and therefore sloughs paint 05 rapidly. Edge-grain boards expose summerwood in narrower bands and hold coatings better than flat-grain boards from the same log. Little can be done, however, to change the type of woods in use, Dr. Browne acknowledges. He urges further research with paints. Aluminum paint as a primer under customary house paints on summerwwds has been found greatly to lengthen the life of the coating.-Science Service