Torbern Bergman as pioneer in the domain of ... - ACS Publications

to check with his teacher before perform- ing the experiments. In any case, care must be exercised to use no more than the quantity of material called...
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photographs. There are several experiments such as the reaction of aluminum with chromic oxide on page 29, igniting a jet of hydrogen on page 49, and the p r e p aration of phosphine on page 61 that can be dangerous to a n inexperienced person. The young eoientist would do well to check with his teacher before performing the experiments. I n any case, care must be exercised to use no more than the quantity of material called for in the experiments. A simple explanation of the principles involved in the experiment in usually given. The first two chapters illustrate and explain the use of basic lahoratory equipment and technique used in a home laboratory. There are nearly 200 experiments under seven general topics: Experiments with Metals, Experiments with Gases, Elements That Are Not Metals, Electrochemistrv and Comhustion. Chemistrv in InAmong the more advanced experiments one lparns how to make hakelite, synthetic rubber, and rayon. The identification of uranium ore and how to make a cloud chamber are interesting experiments found in the atomic energy chapter. I know you will enjoy doing some of the experiments, just as I have, once you start looking a t the book. LESTER KlEFT B n c l r a e ~Umvsnarrr ~ LIW,B."R(I. PENNB~LV*XI*

TORBERN BWGMAN AS PIONEER IN THE DOMAIN OF MINERAL WATERS Uno Boklund, Almqvist & WikseU, Stockholm, 1956. 2 d s . 127 and 131 pp. 12 X 18.5 cm. 15 Swedish crowns each.

IN TAESE beautifully printed little volumes the memory of Torbern Bergman (1735-1784), who accomplished so much in so many fields of chemistry in his short lifetime, has been fittingly honored by the Swedish National Association of Soft Drinks Manufacturers through the republication of his paper "On Acid of Air" (1773) and his "Treatise on Bitter, Seltzer, Spa, and Pyrmont Waters and Their Synthetical Preparation" (1775)in facsimile form in the original Swedish and in an excellent English translation by Sven M. Jonsson. Both the Swedish and the English volume contain also a well-written appreciation of Bergman's contributions to this field by Uno Baklund. Both volumes are well illustrated with a portrait, contemporary views of Upsalrt, and title pages of the issues of Kongliga Vetenskaps A d m i a s Handlingar in which Bergman's articles on this subject originally appeared. Bergman believed that water analyai~ was a subject of great public interest and that "in this liquid substance are sometimes hidden the most vsluablo remedies for many diseases, especially chronic ones. . . ." In his dissertation of 1770, "Chemical (Continued on pnye A490)

JOURNAL OF CHEMICAL EDUCATION

Analyais of the Spring W&rs in Ups& and Vicinity," he had already realized that the presmre of "acid of air" (cat+~on dioxidc) in a water often enhances its effect. Another reason why he investigated mineral waters was his need for them. Although he derived henefit from the imported waters which his phy~irian prescribed, "the cure was too expensive. . .." He therefore mado cornpsrative analyses of nntural imported waters, prepared syathetie waters of similar composition, and even improved upon the natural ones by omitting r e h i n constitnents shown to he useless or harmful. His synthetic waters had tlre advantage too of freshness and lack of "flstncss." To prepare "an xbsohttely pure vehicle for the solid const,itumts" he distilled the purest obtainable snow from mountain peaks. In January 1772 he prepared "Pyrmont water" from sulfuric acid, chalk, sodium earl,anste, and iron filings and tested his product with litmus paper. In 1775, after he had tested the artificial waters successfully on h i m d f , Bergman published, in the "Treatisc on Bitter, Seltzer, Spa, and Pwmont Katers. .," a description of his mothod and apparatus, which were soon adopted in other European countries as well it8 in Sweden. Uno Boklund, after sketching the development of chemical and medical knowledge concerning mineral waters and their analysis, points out that Bergman had slready done much preliminary work in devising analytical methods and apparatus in preparation for the thesis which he defended in 1770. Mr. Boklund empllnsizes strongly that Joseph Priestley, in his experiments on the impregnation of water with "fired air," made extensive use of the experience of his predecessors Joseph Black, David MacBride, Henry Cilvendish, and William Brownrigg. I n all fairness i t should be added that Priestley acknowledged this indebtedness in his "Experiments and Observations on UiKerm t Kinds of Air." P1.iest1e.v had impregnated water with "fixed sir" in the summer of 170i simply hy pouring tho water back and forth from one vessel into mother in the carbon dioxide atmosphere over the fermentation vats of a brewery. I n 1772 he allowed carbon dioxide, prepared from chalk or pounded marble and sulfuric acid, to Imbhle into s. bottle full of water standing inverted in mater. After the College of Ph-sieians had examined the carbonated water and had recommended the trial of it, Priestley published a pamphlet describing his method and apparatus. I n a footnote to the paper on "Acid of Air" Bergman acknowledged receipt of a letter from Priestley roncerning the latter's "Pyrmont C R ~ P I " and pointed out that it could not "rompletely resemble natural water, whirh contains morr substances t,hm iron and mid of air . . ." MARY ELVlR.4 WEEKS I ) l m 0 , r . . YICHIOAN

(Continued on page A5W)

VOLUME 34, NO. 10, OCTOBER, 1957