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THE METROPOLITAN WATER-SUPPLY.

IN the report issued last week on the conditionof the metropolitan water-supply during the monthof October, 1915, it is shown that whereas95’1, 99’9, and 47’6 per cent. of the samplesof raw Thames, Lee, and New River water

respectively contained typical B. coli in 1 c.c.

(or less) of water, 83’9, 52’4, and 89’5 per cent.of the filtered water samples derived fromthese rivers contained no typical B. coli evenin 100 times as much water-namely, 100 c.c. Themonth was fairly dry and seasonable, the rainfallmeasuring 2’06 inches, which is 0’66 inch belowthe average. Compared with previous averages,both the raw river waters and the filtered waters,speaking generally, either deteriorated or showedno change in the light of chemical analysis, whilebacteriological examination showed in the rawwaters fewer bacteria than their respective averages,the filtered waters giving satisfactory results. Theimportance of storage before filtration is againillustrated, and nearly the whole of the supply isnow stored antecedent to filtration. As Dr. A. C.Houston points out, the improved condition of thewater immediately antecedent to filtration is bestexpressed by saying that on the average about one-third of the pre-filtration samples contain no typicalB. coli in 10 c.c. of water.

THE PROTECTIVE POWER OF CLOTHINGAGAINST COLD AND DAMP.

NEARLY all physiological and hygienic researcheson men’s garments as a means of protection againstcold and damp have hitherto laid the principalstress on one condition, that of porosity and

hygroscopicity of the tissue, almost entirely for-getting another condition equally essential-namely,the presence of fatty material and its quantity andquality. In a report recently issued by ProfessorC. Terni in a series of " Medical Propaganda inWar," attention is drawn to the fact that vege-tables which possess only in the smallest degreethe power of producing heat protect their mostvital parts, the huds, with layers of cellulose andwith an impermeable covering. But this protectivelayer is fatty, and therefore it may be assumed thatprotection against cold and damp in nature dependsin a large measure on the presence of these fattysubstances more than on any special qualities of thetissue itself. Professor Terni urges the import-ance, therefore, of more serious attention beinggiven to the amount of fatty material in clothing.Wool possesses naturally both a maximum of

porosity, owing to the conformation of its fibres,and an adequate amount of fatty material, butin process of manufacture it is deprived of its natural fat which would become rancid, and itis therefore necessary to restore its fatty nature bystable fats which become fixed in the fibres andremain adherent even at a low temperature. Com-mercial enterprise has overcome this difficulty, andit is possible to obtain material of fatty wool in acondition best adapted for protection against coldand damp. There are two objections to it, how-ever-namely, expense and weight, and ProfessorTerni is of opinion that cotton composed of twistedfibres, and having a large :content of fatty materialof a much more stable character than that ofanimal origin, can be spun and woven with very

1 Il Morgagni, Part II., Dec. 2nd, 1915.

small loss of this fat. By this method we canobtain one of the most economical of coverings,equal to wool in its efficiency against cold anddamp, and, moreover, with a marked reduction inweight, a point of real importance to all those whohave to work while on the move.

THE GOAT AS A SOURCE OF MILK.

A VERY interesting circular has been issued,amongst others this week, by the Board of Agri-culture and Fisheries, pointing out how in certaindistricts goat-keeping might be extended withadvantage. It is well known that many cottagersand others living outside the area of retail deliveryfind it difficult to obtain milk for their families.The large dairy farms are, as a rule, under contractto supply milk to distributing agencies in towns, orelse they turn their milk into cheese and butter.As the Board rightly says, all the objections whichapply to the keeping of a cow by a cottagerwould be met in the case of a goat. Thefirst expenditure for its purchase is within hismeans, the housing accommodation is reduced to aminimum, the food costs little, and there is nogreat expense to be borne for the maintenanceof the animal. Even in the event of a cow’smilk supply being available, goats may profitablybe kept to supply milk for domestic use. It

is, as a rule, a most wholesome milk, andits flavour, if the food of the animal is regu-lated, is not any real drawback to its employment.Moreover, goat’s milk is easily digested bychildren, and especially infants, and, as is wellknown, it is far less likely than cow’s milk tocontain tubercle bacilli of animal origin. The

average goat will give at its flush three pints of £milk a day, and, on the whole, calculations basedon extreme cost of keep, outlay, and so forth, showthat while a good supply of milk could be main-tained, a very fair profit could be made. The sug-gestion is a valuable one, and the information con-tained in this circular as to how to start goat-keeping,as to the choice of breeds, as to breeding itself,housing, feeding, tethering, milking, and the care ofthe milk, and so forth, should be spread up anddown the land. We append the composition of £

goat’s milk compared with human milk and cow’s.milk :-Goat’s milk: Water 86’04 per cent., fat4’63 per cent., sugar 4’22 per cent., casein 3’49 percent., albumin 0’86 per cent., and mineral matter0’76 per cent. Human milk: Water 88’2 per cent.,fat 3’3 per cent., sugar 6’8 per cent., casein 1 percent., albumin 0’5 per cent., and mineral matter0’20 per cent. Cow’s milk: Water 87’33 per cent.,fat 3’75 per cent., sugar 4’75 per cent., casein 3’0per cent., albumin 0’40 per cent., mineral matter0’75 per cent. It will thus be seen that the com-position of cow’s milk and goat’s milk is muchthe same, although goat’s milk is superior as regardsfat, which is an advantage. Human milk differschiefly from goat’s and cow’s milk in that itcontains a much smaller proportion of mineralsalts and casein.

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THE IRON-BACTERIA.

A VERY interesting article contributed by DavidEllis, Ph.D., D.Sc., F.R.S.E., to the January numberof Science Progress deals with those higher bacteriawhich are almost always to be found flourishingin ferruginous waters. As the organisms growand multiply their mucilaginous outer membranes