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568
THE POPULAR SCIENCE MONTHLY.

Islands, which is partly based on observations made during a visit to the leper settlement on the Island of Molokai in February, 1880. The Hawaiian leprosy does not differ essentially from the disease in Europe and Asia, but its history is known from its origin, and its development there may be traced with greater accuracy of detail than in other countries. It was introduced from China with the coolie-trade, and was first recognized in 1848. Its spread has been furthered by the peculiar habits of the people, particularly in eating, and their close association in their houses, and is contributed to by the exhaustion caused by the use of the intoxicant kava. To this may be added impure vaccination, which was practiced indiscriminately by all classes of people in 1852, and the prevalent licentiousness, which is hardly concealed. All observers agree that the disease is hereditary and that death alone ends it. It is established that it is a specific and well-marked disease—not a form of syphilis—that it exists in two varieties, the tubercular and anæsthetic, which may be distinct or associated, that it is not contagious, but is transplantable, and that men are more liable to it than women. The treatment has heretofore been merely palliative, the most useful drug in affording relief being the bark of the hoang-nan-tree. The most effective preventive of the spread of the disease is isolation. Few of the children born of leprous parents survive infancy and none survive adult age. Hence, is suggested the possibility of stamping it out if the lepers can be kept separated from the rest of the population. The population of the Pacific States are in no immediate danger from leprosy, but the increasing intercourse with China and the Sandwich Islands, combined with prostitution, offers a constant menace, and makes vigilance a duty.

The Real Discoverer of Spectrum Analysis.—Mr. Frank Cowan makes, in the "Pittsburg Telegraph," a strong presentment of the claims of the late Dr. David Alter, of Freeport, Armstrong County, Pennsylvania, who died last September, to be regarded as the real discoverer of spectroscopic analysis. Dr. Alter was born in 1807, and manifested at a very early age an interest in the study of electrical phenomena, and later in chemistry. He invented and perfected an electric telegraph in 1836, which, being more cumbrous than Morse's, and even than Wheatstone's, he never attempted to bring into use. He also invented an electrical engine, and published a paper on electricity as a motive power in 1837. His papers on spectrum analysis were published in the "American Journal of Science" in 1854 and 1855, five years before Kirchhoff announced his discoveries. The first paper, published in the number of the "Journal" for November, 1854, was "On Certain Physical Properties of Light, produced by the Combustion of Different Metals in the Electric Spark, refracted by a Prism." After describing the appearance of the light of the sky, of a petroleum-lamp, of a tallow candle, the flame of alcohol, and the light from heated wire or charcoal as seen through his home-made prism, he gives accounts of the "separate colored bands" which he observed in the spectra of the sparks caused by the break of the galvanic or magnetoelectric circuit, from points of silver, zinc, copper, lead, tin, iron, bismuth, antimony, brass, and combinations of metals. The second article appeared in May, 1855, and was "On Certain Physical Properties of the Light of the Electric Spark within Certain Gases, as seen through a Prism." This paper is explicit, and contains a paragraph suggesting the application of the author's discovery to the detection of the elements in the aurora borealis, shooting-stars, and luminous meteors. An abstract of the first paper was published in Liebig and Kopp's "Chemico-Jahresberichte" for 1854. The second article was reproduced entire in "L'Institut," of Paris, in 1856, and in the "Archives of the Physical and Natural Sciences" of Geneva, vol. xxix, p. 151. A full-page extract from it, containing its most suggestive statements, was also published in Kopp and Will's "Jahresberichte" for 1859. Kirchhoff announced his discovery in the year last mentioned.

Organic Remains in Meteorites.—Professor J. Lawrence Smith expresses a strong disbelief in the alleged discovery by Professor Hahn of organic remains in meteoric stones. He says that, although he has probably examined more microscopic plates of