Page:Popular Science Monthly Volume 7.djvu/137

Rh cost of constructing and maintaining aquaria considerably diminished. This principle is applied in the transportation of living aquarium animals to considerable distances. Take, for example, a fish packed in damp, freshly-gathered sea-weed. Its gills are kept wet by such very thin films of water that their thinness, otherwise shallowness, enables them to be constantly oxygenated by contact with the atmospheric air. Thus the gill-filaments are kept wet and separate from one another, and the blood flows uninterruptedly through them, being aerated as it does so.

The Origin of the Potato.—Mr. Meehan, of Philadelphia, has for eight years cultivated Solanum Fendleri, a solanaceous plant which has much in common with the potato (Solanum tuberosum). His object was to ascertain whether the former could be transformed into the latter by cultivation, and so to settle the vexed question of the origin of our common esculent tuber. It was not till last year that the plant began to vary in the direction of the potato. Previously, the tubers were round, about the size of a large bullet, and rugose from the imperfect tube-cells on the surface. Last season, however, the roots began to resemble those of the potato. They were oval and compressed, and one was an inch wide and two inches long, with a clear, semi-translucent skin, as in the more delicate potatoes. Mr. Meehan, however, does not expect to develop potatoes from his wild solanum; according to him the facts so far obtained do no more than suggest the possibility of the unity of origin of the Solanum Fendleri and the S. tuberosum.

Cultivation of Jute in the South.—The cultivation of jute in the southern portion of the United States seems destined to become, at no distant day, a highly-profitable industry. Notwithstanding the many difficulties and drawbacks of the past season—deluging rains, overflows of rivers, and droughts—it was expected that the harvest in Louisiana would be satisfactory. In a letter to the Department of Agriculture, Mr. Emile Lefranc, of New Orleans, President of the Southern Ramie Association, describes some of the fields as splendid, growing eight feet high, and as thick as wheat. The forthcoming report of the Department will contain a description, with illustrative drawings, of Lefranc's jute-cleaning machine. This machine will produce over a ton of clean fibre per day, with four attendants only. It cleans jute, ramie, and okra radically, and without waste, and it is believed that hemp and flax may also be treated with it with equally satisfactory results.



of Castellamare, Italy, has devised an improvement in pneumatic telegraphs, consisting of an instrument which will serve either as a transmitter or receiver. By means of two such instruments, placed at different stations and connected by a single air-conducting tube, messages may be transmitted in either direction. There is but one dial, which serves to indicate both the signals sent and received, so that the same instrument is made to answer both purposes, thereby dispensing with one of the two required in all other pneumatic telegraphs, and lessening the cost of apparatus. The invention has been patented here.

F.R.S., naturalist of the British Museum, died March 6th, in the seventy-fifth year of his age. He was a voluminous writer on zoological and botanical subjects. He was connected with the Natural History Department of the British Museum for over fifty years. In addition to his strictly scientific work, he took part in the discussion of various questions of social importance, such as public education, prison discipline, the postage system, and the organization of museums and galleries of art.

at Bonn, on the 17th of February, Prof. Friedrich Wilhelm August Argelander, the celebrated astronomer. Deceased was born in 1790, and in 1820 became the official assistant of Bessel at the Königsberg Observatory. From 1845 till his death, he was in charge of the observatory of the Bonn University. His "Celestial Atlas," lately published, ranks among the best works of its kind.

isolated study of any thing in natural history is a fruitful source of error. .... No single experiment in physiology is worth any thing."—Dr. Jeffries Wyman.

is to be prepared for the use of the British Arctic Expedition of next summer, consisting of reprints of papers in the transactions of learned societies not otherwise accessible, and other materials, the 