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Rh of whom were affected with malaria. Again, there is the outbreak of ague at Tilbury Fort in 1872, cited in Parkes's "Hygiene," where thirty-four men out of a garrison of one hundred and three were seized with ague, while the people at the railway station and the coast-guard men and their families just outside the fort entirely escaped. The troops had been supplied with water stored in tanks, collected from the rain-water of the roofs, while the people outside obtained theirs from a spring, the atmospheric conditions in both cases being identical.

The Werdermann Electric Light.—Mr. Edison's announcement of his success in solving the problem of adapting the electric light to domestic purposes has had the effect of bringing into public view a number of other contrivances for producing the same result. Among these, Werdermann's system appears to be perhaps the most promising; the following account of it we take from "Nature": "The principle of Werdermann's invention is that of keeping a small vertical pencil of carbon in contact with a large disk of the same material. In some earlier experiments he found that when he increased the sectional area of one carbon and reduced that of the other he produced an electrical light with the carbons in actual contact, a small arc appearing at the contact-point. The small carbon is a pencil three millimetres in diameter; the upper or negative carbon is a disk of two inches in diameter and an inch thick. The upper carbon is not consumed, so that the waste takes place only in the lower. In his lamp he places the disk uppermost with the pencil vertically beneath it, sliding up a metal tube which acts as a guide and contact. The pencil is kept in contact with the disk by means of chains attached to its lower extremity, passing over pulleys and down again to a counterweight of about one and a half pound. About three quarters of an inch of the lower carbon appears above the tube and is rendered incandescent by the passage of the current between it and the disk. This pencil is pointed, and retains its point all the time of burning. It is between this point and the disk that the small electric arc appears which gives the greater part of the light. In an exhibition of the system, ten lamps were shown in one circuit. The inventor believes that after further experiments he will be able to divide the current into fifty, one hundred, or even five hundred lights. Each lamp can be lighted and extinguished separately without affecting the others."

Dangers of Moldy Bread.—A singular case of poisoning from eating a pudding made in part of moldy bread is reported in the "Sanitary Record." The main facts of the case may be briefly stated as follows: The principal materials of the pudding consisted of scraps of bread left from making toast and sandwiches, and they had been about three weeks accumulating. To these scraps were added milk, eggs, sugar, currants, and nutmeg. The whole was baked in a very slow oven, and was subsequently eaten by the cook, the proprietor of the eating-house in which it was prepared, the children of the proprietor, and two other persons. All of these became violently ill, with symptoms of irritant poisoning. One of the children (aged three years) and one of the adults died. The necropsy of the body of the child caused the medical men to suspect poisoning, and accordingly the viscera, together with the remnant of the pudding, the materials used in making it, the matter vomited, etc., were sent to a chemical analyst, Mr. Alfred Allen, for examination. He made tests for several poisons, but without positive result. A puppy was fed with the pudding for two days without any poisonous effect. He was then led to look for ergot in the pudding, and was soon startled to find unquestionable evidence of its presence, as far as the chemical reactions went, though he was unable, with the aid of the microscope, to detect any actual ergot. From these facts Mr. Allen infers that the reactions hitherto supposed to be peculiar to ergot are common to other poisonous fungi.

Steering of Ocean-Steamers.—Among the reports of committees to the British Association at Dublin was one on the steering of screw-steamers. This report declares it to be an invariable rule that, during the interval in which a ship is stopping herself by