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426, which was most carefully planned and took place in a climate that is exceptionally dry and hygienic, there was no abatement of typhoid fever. In the case of an outbreak of malignant dysentery described by the author in a previous paper, taken at its height, not a new case occurred after measures were adopted that made conveyance by flies impossible, although there had been fresh ones every day for some time previously. Another more recent "lively epidemic" of typhoid mentioned by the author was ended in a day by measures directed against conveyance by water. "When flies are responsible, there are little neighborhood epidemics, extending in short leaps from house to house, without reference to water supply or anything else in common. But when water is at fault the disease follows its use wherever it may go.… Epidemics spread by flies tend to follow the direction of prevailing warm winds, as though the fly, wandering outdoors after contact with the source of infection, had drifted with the wind, but nothing of the sort is perceptible in the case of water-borne disease."

Pottery Making and Lead Poisoning.—The report of Professors Thorpe and Oliver on the subject of the employment of compounds of lead in the manufacture of pottery, especially in its relation to the health of the work people, has just been issued as an English blue book. It appears that of the total male workers in the year 1898, 4.9 per cent became "leaded," while of the female workers the proportion was 12.4 per cent. It is stated that in the last six months many successful attempts have been made by the manufacturers to substitute a leadless glaze, and there seems no doubt that glazes of sufficient brilliancy, covering power, and durability are now within the reach of the manufacturer. The exclusion of women from certain parts of the work, except where leadless glazes are used, is advocated, and also various expedients for preventing the absorption of the lead by the skin, such as rubber gloves or "dipping" tongs. Their general conclusions are as follows: "That by far the greater amount of earthenware of the class already specified can be glazed without the use of lead in any form. It has been demonstrated, without the slightest doubt, that the ware so made is in no respects inferior to that coated with lead glaze. There seems no reason, therefore, why in the manufacture of this class of goods the operatives should still continue to be exposed to the evils which the use of lead glaze entails. There are, however, certain branches of the pottery industry in which it would be more difficult to dispense with the use of lead compounds. But there is no reason why, in these cases, the lead so employed should not be in the form of a fritted double silicate. Such a compound, if properly made, is but slightly attacked by even strong hydrochloric, acetic, or lactic acid. There can be little doubt that, if lead must be used, the employment of such a compound silicate—if its use could be insured—would greatly diminish the evil of lead poisoning. The use of raw lead as an ingredient of glazing material, or as an ingredient of colors which have to be subsequently fired, should be absolutely prohibited. As it would be very difficult to insure that an innocuous lead glaze shall be employed, we are of opinion that young persons and women should be excluded from employment as dippers, dippers' assistants, ware cleaners after dippers, and glost placers in factories where lead glaze is used, and that the adult male clippers, dippers' assistants, ware cleaners, and glost placers should be subjected to systematic medical inspection. In the 1893 report the medical members of the committee expressed the opinion that 'many old factories are wholly, or in part, unfit in a sanitary point of view for occupation,' and they suggested that 'there should be some authority to close them, or whatever part of them is condemned, on the same principle as dwellings are declared uninhabitable.' We share this opinion and we concur in the suggestion. Certain of the factories we have inspected are in the last stages of dilapidation, and it appears to us to be well-nigh impossible to introduce into them such rearrangements or additions as are required by the amended special rules."

The Longevity of Animals.—The following interesting table, showing the periods of maturity and the full term of life of various animals, was prepared by