THE POPULAR SCIENCE MONTHLY.
folding of the leaf, as well as the intrusion of the glands, was discovered by Roth in 1779. The only real addition to our knowledge—this old knowledge, recently reproduced—is that contained in the latter part of Mr. Bennett's communication, which is to the effect that Drosera acts upon bits of raw meat just as upon a living insect, but is motionless toward inorganic bodies, and, in his experiments, to bits of wood and of worsted. In the published report of the communication no allusion is made to the history and record of all these discoveries, but Prof. Gray claims for Mr. Darwin the credit of having been the first to discover this difference of behavior of the drosera-leaf to different substances. He says that there are other still more curious observations and experiments of Darwin's upon Drosera and Dionæa, which it is hoped will soon be published.
Ocean-Steamships.—A writer in the Evening Post notes some of the principal shortcomings of the ocean-steamship of the period, and offers some practical suggestions as to the proper construction of a passenger-steamer. The ocean-steamer of to-day is simply a huge freight-boat. She is somewhat larger, and perhaps a trifle swifter, but certainly not any safer, than when she first crossed the Atlantic some thirty years ago. It would seem absurd if our railroads had no passenger-cars, and we had to travel about the country strapped on to the roof of a freight-car. Ocean-travel is quite as absurd, and even more dangerous, for our tier of state-rooms is strapped to the top of a heavy iron box, loaded with heavy freight, which, in the event of a sudden blow, goes to the bottom as if it were made of glass. According to the writer in the Post, the passenger-steamship should be of about the same length as at present, but broader and shallower, with lines adapted, not to carrying capacity, but to speed; the chief novelty, however, being that the entire hull, excepting the spaces required for engines and coal, would be filled up with very small air and water-tight compartments or cells—enough to make the ship a gigantic life-preserver. All the state-rooms and quarters would be on the main-deck. The cellular construction of the vessel would add greatly to her strength, while her lightness would admit, at least in ordinary weather, of great speed, and her model would greatly diminish the rolling so provocative of sea-sickness.
As regards the question of expense, while the first cost and daily outlay would net exceed those of the present style of steamer, the passenger-steamer could make twice as many trips in the year, for she would not only be actually faster, but would save much time between voyages which is now spent in discharging and receiving cargo; for the same reason, after landing her passengers, she could start again in a day or two on another trip. Such a vessel might be disabled by collision, but it is hardly possible that she could be sunk by any form of accident that we are familiar with.
Tarantism.—Tarantism is the title given by physicians to an epidemic nervous disorder which prevailed in Italy, and more particularly in Apulia, during the middle ages. It was supposed to be caused by the bite of the tarantula, a species of spider found in Southern Europe, and very plentiful in the vicinity of the city of Taranto, whence it derives its name. The disorder, whether caused in the first instance by the bite of this spider or not, was capable of passing from subject to subject by a sort of sympathy, and thus the affection would spread to hundreds and thousands of the population, without distinction of sex or age. Analogous nervous diseases, known as St. Vitus's dance, or St. Guy's dance, prevailed in Germany, France, and England. A recent writer on "Mental Disease," W. A. F. Browne, gives the following account of these singular affections:
"In all these affections," says he, "which spread over great masses of the population, Teutonic and Celtic, children and octogenarians alike, there were observed wild and exuberant excitement, delusion, and antipathies, with uncontrollable impulses to run or leap, all such movements ultimately passing into dancing, which was generally aggravated, though sometimes mitigated, by music. These dancers were impelled sometimes by imitation, sometimes by fanatical exaltation, sometimes by terror and the fear