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Rh high out of the water." A month later, the people were awakened between one and two o'clock in the morning by a series of shocks. A frantic terror, causing neglect of domestic concerns, riot, and a suspension of business enterprise, possessed all classes for several weeks afterward. It was heightened by a prediction that a third earthquake would occur in April, and all who could left the city; others spent their nights out of doors. A quack made his fortune during the panic by selling pills which he warranted to be a sure preservative against injury by earthquakes. Only slight shocks have since been felt in the metropolis.

Impure Air and Disease.—Dr. J. Ward, health-officer of an English sanitary district of considerable extent and population, has given in the "Sanitary Record" an account of a large number of instances which have come under his immediate observation, in which impure air, arising either from defective ventilation or noxious surroundings, has appeared to be directly associated with the production of diseases of the lungs and other organs. Of eight fatal cases of pneumonia occurring within a year among children and persons in middle life, in all but one the air was defiled from some neighboring source of filth. In about ninety fatal cases of diseases of the respiratory organs, other than pulmonary consumption, most of which were acute or subacute, undoubted defects of ventilation existed. In some cases there was no fireplace or air exit in the room; in some, such opening, where it had existed, had been closed tight; in some the bed, with many in it, was in a close corner; in others the air was defiled by some neighboring household or farm nuisance. Similar defects were observed in nearly all of thirty cases of disorders of the lungs following measles; in forty cases following whooping-cough—in sixteen of which last, "filth influence from immediately contiguous byre, pig-styes, stable, water-closet, or sewer, was noticed." The sanitary investigation of the interior and surroundings of houses where inflammatory affections of the brain have occurred has forced upon Dr. Ward the conclusion that diseases of this class are also frequently, and, it may be inferred, causatively, associated with similar insanitary conditions. In twenty-eight fatal cases of this nature, seventeen cases of tubercular meningitis, and twenty-two cases of convulsions in children, the air was either confined or polluted. Dr. Ward draws from these observations the obvious lesson that it should be the aim of sanitary administration to secure for each habitable room, especially in the crowded cottages of the poorer classes, some suitable provision for a constant change of air. Particularly should care be taken in fixing the position of the bed so that it shall not be in a close corner remote from the influence of the door, window, and fireplace, but should be near some opening through which a constant circulation may be relied upon. In transforming old houses, the provision of fresh air, now neglected and too often prevented in the arrangement of the partitions, should be carefully looked after—else the sanitary condition of the house may be made worse than it was before.

An Improved Filtering Apparatus.—Some experiments that have lately been made in France on the working of the Farquhar apparatus for filtering sewage have been attended with quite satisfactory results. One of the chief obstacles to the purification of foul waters by filtration has arisen from the accumulation of an impervious, slimy deposit on the matter which prevents the liquid from reaching the filtering surface. The Farquhar apparatus is designed to obviate this difficulty by means of a provision for the continuous removal of the slime. The filter-bed, which may be composed of any suitable material, is contained in a closed cylinder in which is worked a cutter-plate continually scraping off the top of the deposit. The liquid to be filtered is forced in through a hollow in the screw-spindle by which the cutter plate is worked, direct to the underside of that instrument, where it is uniformly distributed over the surface of the filter-bed. The cutter-plate is caused, by suitable machinery, to revolve during the process of filtration, and may also be made to descend if that is desired. The accumulating deposit is scraped off, and forced up the inclined plane of the knife, as shavings are forced up through a carpenter's plane, to