Popular Science Monthly/Volume 45/August 1894/Notes


The summer meeting of the Northwestern Electrical Association was to be held in St. Paul, Minn., July 18th, 19th, and 20th. A larger number of attendants was expected than were present at the last meeting, including representatives from Illinois, Iowa, Michigan, Wisconsin, and North and South Dakota. An excellent programme was prepared, and speakers were invited from among the most expert representatives of the profession.

The essential oils were held in high esteem by the ancients, but lately seem to have been forgotten in the multitude of new discoveries. The power of many of them to destroy bacteria has, however, been demonstrated anew by M. Chamberland, M. Cadéac, and M. Meunier, and M. Blaizot and M. Caldagues have found in them bactericidal powers even greater than they had been supposed to possess. The essences found by these gentlemen to be most active are those of cinnamon, lavender, marjoram, cloves, geranium, vervain, and tuberose. The simple exposition of their vapors is sufficient to destroy in an hour such microbes as those of pus and cholera, and six minutes' exposure effects a manifest attenuation of their activity.

The method of purification by distillation in a vacuum, which has hitherto been little employed, except with mercury, has been applied by Prof. G. W. Kahlbaum, of Basle, with great success to potassium, sodium, selenium, tellurium, cadmium, magnesium, bismuth, and thallium, while the experiments with zinc and manganese have so far been unsatisfactory. Judging by spectrum analysis, an extreme degree of purity was obtained. Thus, thirty-five ines disappeared from the spectrum of tellurium, showing, the author believes, the absence of substances which modify the spectrum of the purest metal obtainable by other processes.

Two living German princes have distinguished themselves by becoming practicing physicians—Duke Karl Theodor, of the royal house of Bavaria, having completed ii course of study, has made a specialty of eye diseases as they occur among the poor, and in April, 1893, successfully performed his two thousandth operation for cataract. Prince Louis Ferdinand, his cousin, besides being engaged in practice, works in the laboratory, and has recently made the etiology and pathology of pleurisy objects of special clinical and bacteriological studies. He has lately published a monograph concerning twenty-three patients suffering from pleuritis who came under his observation.