VOL.8, NO. 7
CORRESPONDENCE THE ICONOCLAST-CORRECTIONS
DEAR EDITOR: In the last issue of the JOURNAL I enjoyed the article entitled "The Iconoclast," by FREDERIC WALKER;but I wish to bring to your attention a slight but unfortunate error made by the author in the translation of the motto of Paracelsus, "Alterius non sit, p i suus esse potest," which was rendered, "He who is not able to be his own will be another's." This misses the point of experimental science, the motto of which, as expressed by Paracelsus, is "Whoever can be his own, let him not be another's.'' JOHN E. RICCI NEWYORK UNIVERSIW UNIVERSITY HEIGHTS, N. Y.
DEAREDITOR: Like Paracelsus I find myself questioned on the subject of my Latin. Mr. Ricci is quite right and his translation is better and more accurate than my own version of the motto. There is also another correction to which I should like to call the attention of the readers of my paper. Twice in the article (pp. 890 and 893) a statement appears to the effect that Galen was probably driven in exile from Pergamum by the doctors of his time. The statement should be corrected t o read that he was driven from Rome. This correction was made before the publication of the article but i t was received too late to have i t included in the May JOURNAL. FREDERIC WALKER 217 HAMILTON AYE. NEWBRIGHTON STATEN ISLAND, N. Y.
A COURSE IN ELEMENTARY BLOWPIPE ANALYSIS AS A FUNDAMENTAL LABORATORY PROJECT IN HIGH-SCHOOL CHEMISTRY The chemistry course used in Orange Union High School, Orange, California, features an elementary course in blowpipe analysis. This supplementary course, which is somewhat of an innovation in high-school chemistry, was introduced as an experiment by our chemistty instructor, Mr. Vernon C. Shippee. The students have enjoyed their work with "unknowns" to such an extent that this feature of the course has been retained permanently.
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The reaction of the students toward this work in blowpipe analysis is, as a rule, enthusiastic. This type of work is very fascinating and a large percentage of the students become greatly interested in the course and follow it through with great zest. In fact, the interest displayed in this work is so great that a "deadline" for finishing the work in blowpipe analysis is almost unnecessary. In order that the students may not work in the dark they are issued a copy of "Notes on Blowpipe Analysis," by Dr. Nicholas Knight. After they have read this pamphlet through, the instructor gives a lecture demonstration on the use of the book. This demonstration consists of the analysis of some typical compounds, calling on the students to follow the course of the analysis by checking the key references in the pamphlet. It is presumed that by now the students have enough general knowledge to do the work by themselves. They are, therefore, issued five "knowns," or substances, the composition of which is known to the class. The composition of these substances must be verified and the written tests, or proofs, of the analysis must be submitted to the instructor. At this point the instructor demands accurate, clean-cut work. If the students learn how to use the "little red hook" intelligently and systematically when working their "knowns," then their work will be much easier when they tackle their "unknowns." The five knowns are, of course, selected to amplify the range of tests shown in the lecture demonstration. The students are now ready to try their first unknowns. Two are issued by the instructor to each member of the class. These two unknowns must be correctly analyzed before any more are issued. The correct write-up of the analyses must he handed in. The issuing of the unknowns two a t a time allows the student a little more judicious use of his time, and cuts down on the amount of detail work required of the instructor. On these first unknowns the instructor frequently helps the students and corrects errors that arise from faulty technic due to lack of practice in the work. He also impresses upon the students the folly of slipshod work and the value of careful observation of gaseous products, peculiar odors, significant colors, or any other peculiarities exhibited by the substance being analyzed. In issuing samples the instructor uses the utmost secrecy. The unknowns are kept in one-ounce bottles which are emptied rapidly and are changed from time to time. The instructor keeps the key list to the unknowns and no one but he or his assistant has access to it. Each student is required to keep a small notebook in which are recorded the following data concerning the unknowns: chemical name; common name, if any; formula; analysis. Under "analysis" the student is required to write up any difficulties encountered and also the peculiarities exhibited by the various compounds. Slipshod or incorrect write-ups are
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returned and must be rewritten correctly before any grade is given. A sample write-up follows. I. Cobalt Sulfate CoSO, No common name. A. A small portion of the substance heated on a clean charcoal block yielded a dark blue to black residue. A speck of the original substance is now fused with a clear borax bead, and imparts to the bead a blue color, showing the presence of cobalt. B. A small portion of the substance is put in a clean, dry test tube and is treated with concentrated sulfuric acid. The substance remains inactive, even when heated, although the color changes from reddish to blue, due to the dehydrating action of concentrated sulfuric acid. C. A water solution of the substance when treated with barium chloride solution yielded a white precipitate, insoluble in hydrochloric acid, confirming the presence of a sulfate.
As a student who has just finished this course in unknowns the writer feels safe in stating that the course is of inestimable value. First-hand knowledge is gained as to the basic laws of analytical chemistry. Chemical equilibrium, and its displacement by heat, knowledge of solubilities, and observation of gaseous products are some of the factors gained from the course. The course also makes an ideal basic foundation for more advanced work in analysis. If the student does not go on to college the course is still of great value. The average person in daily life frequently needs to know or would profit greatly if he did know the composition and reaction of various chemical compounds. This course fits a person so that he is able, if need be, to analyze any simple compound he runs up against. The writer feels that an elementary course in blowpipe analysis should be included in all high-school chemistry courses.
