Page:Popular Science Monthly Volume 29.djvu/149

Rh it is described as a mighty river like the others. The name, which means "having running water," seems to mark it as a constant as well as powerful stream, and is applied as an epithet to the Indus and other great rivers. The volume of the stream may have been partly affected by the changes which the country in general has undergone, but a considerable part of the discrepancy must be attributed to the poetic character of the Vedas and the imperfect knowledge which the Sanskrit people may have possessed of the character of this river. In the later writing, dating from about the sixth century the Saraswati is said to sink into the earth and to pass underground to join the Ganges and the Jumna at their confluence. The people had then gone farther into the country, and had become better acquainted with the Saraswati.

Influence of Direct Solar Heat on Vegetation.—Mr. M. Buysman has published a paper on the "Influence of Direct Sunlight on Vegetation." On account of the constant high temperature in the tropical regions, plants there are less dependent on direct solar heat than in the temperate and frigid zones, but there are some even there which require this condition for their luxuriant growth. Among these are the date palm and the sugar-cane. In the warm temperate zone, the orange grows best in the direct sunlight, and the vine requires the heat of after-summer to ripen its fruits. Everywhere, whether in the warm or temperate region, corn is grown with success wherever there is in summer direct sunlight enough to ripen its grains. On highlands, the influence of insolation is very much increased. But the solar warmth of the after-summer is necessary to ripen the fruits of the most important plants; and it is for lack of this, and not from any deficiency in the mean temperature, that the vine can not be cultivated successfully in cloudy England. The limit of corn cultivation ascends on the continent generally farther to the north than on the shores. In Norway, it reaches 70; at Fort Norman, Canada, 65°; at Yakutsk, Siberia, 62°; on the northeast shores of Asia and the northeastern shores of America, nearly to 50°; on the western shores of America, 57°. Nowhere else is the influence of insolation more distinctly observed than in the Arctic regions. Richardson remarks, of the vicinity of Slave River, near 60° north latitude, that he had never felt the heat of the tropics so oppressive as he experienced it on some occasions in those regions, though the sun's rays are there always horizontal instead of vertical, as is the case in the tropical countries. This is because in summer the sun rests above the horizon. In Nova Zembla the vegetation is, in places exposed to the sun's rays, "like an arctic flower garden," for the surface of the soil is not covered with grass as in the temperate regions; and the flowers are of a much greater size than the leaves. In the Tundra of Siberia, on the declivities of hills sheltered from the winds and exposed vertically to the sun's rays, the same herbaceous vegetation, with its large, splendidly colored flowers, is observed, but this is not the case in plains where the sunlight in its horizontal direction can not have so much influence on the vegetation of the frozen ground. Therefore these plains are in general really deserts, covered only with moss. Insolation is also the cause of the rich vegetation in some parts of the mountains in the temperate zone. Even in the most northern regions there can be a rich vegetation where the plants in sheltered localities are exposed to the sun. Several instances are mentioned by Mr. Buysman in which plants have been found blooming in these regions while their roots were frozen.

A Bee Nuisance.—M. Delpech, of the Hygienic Council of the Department of the Seine, has published a report on the damage done by bees and the dangers resulting from the existence of apiaries in the city of Paris. The bees, it appears, have become a real and formidable nuisance in some parts of Paris, especially in the neighborhood of the sugar-refineries and the railway-stations, where hundreds of stands are kept. The extent of their depredations upon the Say sugar-refinery is estimated at 25,000 francs, or $5,000, a year. A glass filled with sirup will be emptied by them in less than two hours; and, if a trap is set, more than a hectolitre, or nearly three bushels of them, may be caught in a day.