Page:Popular Science Monthly Volume 37.djvu/153

 flora have been obtained by Mr. Hallick from the ferruginous sandstone on the shore at Tottenville. The occurrence of copper, derived from the decomposition of pyrites, in the limonite ore beds at Todt Hill is mentioned. Several well-defined nearly driftless areas north and west of the terminal moraine illustrate an interesting feature of glaciation. 

Geological Map of New York City and its Environs is the only map giving in detail the geology of the entire region (fifty-five by sixty-eight miles) surrounding the metropolis; it is compiled with great care from separate sources, some of which are not easily accessible, and some are unpublished; it exhibits the relations of many geological systems and series east of the Alleghanies; and shows striking features connected with the Glacial age, the terminal moraine, and the ancient (now submerged) channel of the Hudson River. A pamphlet of explanations accompanies every copy. A few copies of the second edition of the map still remanremain [sic] for disposal at ten dollars each. No more are likely to be published. Address Prof. Martin, at Rutgers Female College, West Fifty-fifth Street, New York.

remarks, in the West American Scientist, on the prominence of the great variety in rock-lichens in producing a pleasing effect in the scenery of Lower California. Red, yellow, gray, and white are the prevailing colors, and the whole side of a cliff is often covered by lichens of the same tint. Quartz, however, is not a favorite rock with the lichens, and consequently is seldom concealed. The lichens frequently imitate, in coloring, the natural hue of the rocks on which they are found.

by Mr. George F. Kunz, the distinguished mineralogical expert of the house of Tiffany & Co., on the Gems and Precious Stones of North America, is announced for publication by the Scientific Publishing Company, New York. It will be a popular description of the occurrence, value, history, and archæology of precious stones in America, and of the collections in which they exist, with a chapter on pearls. The several species and varieties are described systematically. The work will be sold at ten dollars a copy.

of Smyrna, has reported favorably on the results of a season's experiments in rearing silk-worms on mulberry-trees, under muslin screens, in the open air, using the regenerated Bournabat graine. They show that the regeneration was thorough and complete, enabling the worms to endure the low temperature of 45° F., with storm and wet for ten consecutive days. The proportion of satiné or satin-like cocoons was extraordinary—fifty to two hundred and ninety-four in all. A somewhat similar trial made in India some years ago was successful experimentally but not financially. In this case the worms, under calico screens, ate along the hedge at their will, new relays taking the place of the old ones as the parts of the hedge over which they had eaten recovered their leaves.

water was substituted for spring water in one of the quarters of Paris several times last summer. In every instance, according to the "Semaine Médicale," an increase of typhoid fever was observed. The quantity of spring water brought to Paris being insufficient for the demand, the Council of Public Hygiene and Health has determined to expedite the labors for the new supply from springs recently bought by the city, and to insist that the use of the present spring waters be limited to food purposes.

will publish soon, Introduction to Systematic Botany. By Charles E. Bessey, professor in the University of Nebraska, and author of Bessey's Botanies in the American Science Series.

recently informed the French Academy of Sciences that the use of the metric system had in 1887 become compulsory in countries having an aggregate population of 302,000,000, being an increase of 53,000,000 persons obliged to use it in ten years; use was optional in countries having nearly 97,000,000 inhabitants; and was legally admitted and partially applied in countries having an aggregate population of 395,000,000. The systems of Japan, China, and Mexico are decimal but not metric. Hence the metric system is legally recognized by 794,000,000 people and decimal systems by about 474,000,000 others.

the Hungarian trade law of 1884, every commune in which there are fifty or more apprentices must provide for their education, and afford special courses of instruction. The apprentice schools in Buda-Pesth contain a preparatory class, provide a course of three years, and are chiefly designed to educate apprentices for the higher trade schools. Each district of the town must have at least one apprentice school. No class is to have more than fifty or at most sixty pupils. Deserving pupils are promoted at the end of each year. In the other towns and counties of the kingdom there are 229 apprentice schools, with 1,237 teachers and 38,081 pupils.

Swedish Oyster-culture Society is trying to acclimatize American oysters from Connecticut on the coast of the province of Bahus. The young oysters seem to thrive well.