VOL.0, No. 5
CH&MIC& TRAINING *OR AGRICUI.TUR&
893
tioned that economic factors play a major part in the way that such material may be used. In many cases the technology has been worked out very satisfactorily, but the possibility of developing an industry depends upon many factors such as climate, location, commercial development, etc. The possible utilization of agricultural products and residues should be impressed upon the student who is specializing in the field of agriculture. Whether taught under the title of agricultural chemistry or embodied in a series of courses under other designations is of little consequence. It is true that the criticism may be made that this is not agricultural chemistry in the light of prevailing definitions, but is a phase of industrial chemistry. Such criticism is well founded but may be answered by the statement that the farmer must have and does have an interest in the industrial utilization of his products if he, as a class, is to prosper. He is wakhg up and is forcing the farm leaders to develop an interest. Inquiries directed to the agricultural colleges and to the U. S. Department of Agriculture indicate the lack of general information upon the subject and the opportunity for the researcher and teacher of chemistry. Two groups of scientists are taking a more active interest in agriculture, the agricultural engineer, who is studying farm machinery with the idea of reducing man-labor upon the farm, and the chemist, who is giving special attention to the industrial utilization of agricultural products and residues. The work so far accomplished indicates the great possihilities for the future and these possibilities should be s h r e d by the teachers of chemistry with their students who are interested in agricultural development.
The Marking of Laboratory Vessels. An interesting paper was read by Mr. A. W. Knapp a t the annual meeting of the Birmingham and Midland Section of the Society of Chemical Engineers held in Birmingham, March 14tb, on the marking of laboratory vessels. I t had become, he said, a common practice on the part of manufacturers to leave a roughened patch on resistance glass vessels which would take a penal mark very well, but where this roughened patch was not provided, marks could be scratched on beakers, or flasks, with diamonds. The marks, however, were not easily seen, and, on heating, there was a danger of cracking. Waterproof Indian ink had been used, but this tended to crack off the glass. Grease pencils were very useful for marking beakers, etc., but the mark somewhat easily rubbed off. To mark beakers in which butter or fat had been melted, he had found nothing so good as a colored spirit solution of shellac, used as ink. Where one had to regraduate pipets or flasks, it was often difficult t o retain a clear and distinct mark. A good method was t o fill the mark with a little ordinary ink and then cover with a small amount of Canada balsam. When allowed t o dry and harden, this would remain on the glass for years. For marking tins, the shellac ink described above would be found very useful. An aluminum pencil was useful for marking porcelain vessels. Cobalt nitrate was effective and much cheaper.-Chem. Age, 20, 278 (Mch. 23, 1929).
