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 was ever imparted by a book from a circulating library, and hence the question had to be discussed simply as one of theory. The doctors differed, of course, some of them asserting the risk of contagion to be great, while others held it to be nil. The conclusion reached by the committee is that, "while there may be a possibility that contagious diseases may be transmitted by books of a circulating library, the real danger of such transmission is very small." Nevertheless, they recommend to the directors of the library "to act under the advice of the Commissioner of Health, and adopt such regulations as he had suggested, namely: that he furnish to the library, whenever he thinks proper, a list of the premises infected with contagious diseases, and of their residents; that no books be loaned to such houses until they are reported by the health office to be free from contagious diseases, and that all books returned from such houses during this period be disinfected before they are replaced on the shelves of the library."

Bird-Reasoning.—The first winter after the erection of a telegraph line on the coast of Antrim, Ireland, numbers of starlings migrating from Scotland were found dead or wounded on the roadside, they having, evidently, in their flight in the dusky morning, struck against the wires. Strange to say, during the following and succeeding winters, hardly a death occurred among the starlings on their arrival. The inference drawn from all this by a writer in "Nature" is that "the birds were deeply impressed and understood the cause of the fatal accidents among their fellow travelers, that previous year, and hence carefully avoided the telegraph wires; not only so, but the young birds must also have acquired this knowledge and perpetuated it—a knowledge which they could not have acquired by experience or even by instinct, unless the instinct was really inherited memory derived from the parents whose brains were first impressed by it."

Habits of the Thresher-Shark.—Having received a fine specimen of the fox, or thresher-shark, Mr. Frank Buckland sends to "Land and Water" an account of all he has been able to learn concerning the habits of that animal. Premising that what he says has to be taken with many "grains of salt," we subjoin the main points of his communication. This shark, it appears, is called "the thresher," from the power it has, in company with the sword-fish, to destroy a whale, by jumping into the air and striking the whale with its tail, the sword-fish in the mean time striking the whale from beneath. Mr. Buckland has never seen a thresher hunting mackerel, but believes that this shark "rushes into a shoal of these fish, and lays about right and left with his long tail; when the frightened mackerel are endeavoring to fall into their ranks again, the shark has a good opportunity of seizing them one by one." Of the contests between thresher-sharks and whales he gives the following animated account, on the authority of one Captain Hill, and in that worthy skipper's own words: "The thresher-sharks just do serve out the whales. The sea sometimes is all blood. A whale once got under our vessel—the Hurricane—to get away from these threshers, and when she was there we was afraid to throw a rope overboard, almost to walk about, for fear she should chuck her tail and punch a hole in our vessel. She was full length, in water as clear as gin, right under our bottom, and laid as quiet as a lamb for an hour and a half, and never moved a fin. Where they had been a-threshing of her, the sea was just like blood. I have seen these 'ere threshers fly out of the water as high as the masthead, and down upon the whale while the sword-fish was a pricking of him from underneath. There is always two of 'em—one up and one under; and I think they hunt together, and you can see the poor whale blow in great agitation; and I be bound the pair of them don't leave him till they have had their penn'orth out of him. I don't think they leaves him till they kills him."

Cost of the Proposed Lake in Algeria.—M. Roudaire, the engineer in charge of the preliminary surveys for flooding the Algerian shotts (dried up lake-beds), estimates the cost of the proposed work at not exceeding 20,000,000 francs. It is only necessary to cut through the narrow isthmus separating the head of the Gulf of Gabes