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Feb. 9, 1882 | 
NATURE 
35! 
the metal, in the process of heating and cooling. This he has 
shown to be unfounded, by heating steel (previously deprived of 
all occluded gas) to bright redness in a vacuum tube, and then 
plunging it in mercury, when it was found to harden just as 
usual. The same followed when a coil of wire was heated zx 
vacuo by an electric current, to expel the gas, and then quenched 
in mercury, 
The first paper read was by Mr. J. J. Tylor, on meters for regis- 
tering small flows of water. The many forms of water meter 
in use are sharply divided into two classes: piston meters, in 
which the water is made to flow into a cylinder under a piston, 
and to escape when the cylinder is full, the number of cylinder- 
fuls being measured; and inferential meter-, in which the 
water is made to turn a fan of some kind, presumably at the 
same speed as that of the water it-elf, and the number of revo- 
lutions of this fan is measured. The latter class has often been 
supposed to be less reliable than the former, especially when the 
quantity passing is small; but the paper gives the results of 
several comparative experiments, which show that an inferential 
meter is at least as accurate as a piston meter for all except the 
very smallest flows, and that for these neither form is fully to be 
depended on. In practice, however, it is found that, even in 
small tenements, little or no water is drawn at so slow a speed as 
fo render meters unreliable. Various tables were given showing 
the great advantages of the meter as detecting waste, the amount 
of which, under our present water system, is enormous. Good 
reason is given for believing that ten gallons per head per day in 
small houses, and fifteen in large houses, is an ample allowance 
for the real wants of the population; and yet twenty-seven gal- 
lons per head is the regular supply of the London water com- 
panies. This is probably the mo:t gigantic specimen of organised 
waste in the world. The means of stopping it are well within 
the compass of science, and the expense would nt be very great ; 
but with the present anarchy in everything connected with metro- 
politan government, it is, we fear, hopeless to expect the matter 
to receive attention. 
To prevent this waste it is not necessary (as Mr. Tylor pointed 
out in the discussion) to place a meter in every house. Although 
many Continental towns are sup lied on that system, it would be 
difficult of introduction in London, and it may be questioned (as 
various speakers did question) whether it would be worth the 
expense. The ‘‘ district meter’’ system practically accomplishes 
the same end without this difficulty. On this system a meter is 
connected with a train of clockwork and drum, so as to register 
the amount of water passed during successive intervals, say of 
ten minutes each. The consumption in the different districts of 
a town, each containing some hundred houses, is measured for 24 
hours each, by simply placing the recording meter successively on 
the mairs supplying them. If any of the diayrams thus obtained 
show special anomalies, the cause can be inquired into: for 
instance, if a district shows a large quantity of water passing 
in the small hours of the night, it is obvious that there is serious 
leakage somewhere ; and the inspector proceeds to make a noc- 
turnal tour, and to listen at the stopcocks of each house succes- 
sively, by which means he can soon detect where the fault lies. 
In instances given by Mr. Tylor, the use of this simple plan had 
been effectual in reducing the consumption by fully one-half in 
particular districts. The system has been applied to the Houses 
of Parliament ; and the consumption of water during some of the 
prolonged debates of las: session has thus been recorded for the 
benefit of posterity. 
The second paper was by Mr. A. A. Langley (engineer to the 
Great Eastern Railway), on the system of dredging introduced 
by M. Bazin, the celebrated hydraulician, on the rivers of 
France. Nothing can be more simple than this arrangement. 
An ordinary centrifugal pump is worked on board the dredger, 
and a flexible pipe leads from the pump to the bottom of the 
water, where it terminates in an elbow-shaped nozzle.. The 
sand and gravel is sucked up the pipe, passes through the pump, 
and is conveyed along an open channel to the side of the 
dredger, where it falls; into a hopper barge or is otherwise 
disposed of. On this system the water pre-sure, as will be 
seen, is used to facilitate the raising of the sand t» the surface ; 
whereas in all other dredgers it is a hindrance rather than other- 
wise. It thus forms an excellent adaptation of scientific prin- 
ciples; and though not applicable for clay or hard ground, is 
much cheaper and more rapid than other forms in the removing 
of sand and shingle. It has also the great advantage that it can 
be worked in rough water, since a moderate rise and fall of the 
vessel does not affect the flexible pipe. 
‘There is another point of interest in connection with this 
dredger. When first started at Lowestoft it was found impos- 
sible to make it work with anything like speed or economy, 
owing to the rapid wear of the cheeks and blades of the pump, 
which were cut by the sand exactly as glass is cut in the sand- 
blast process. After many trials the evil was stopped by the 
simple process of protecting the blades of the fan by pieces of 
thick india-rubber, which from its softness and elasticity yields 
to the cutting action, and thus escapes much injury itself, while 
it prevents all injury to the cheeks. This peculiar property of 
india-rubber has, we believe, been previously utilised in connec- 
tion with the sand-blast process, but it has never been adopted 
on so large a scale, and it certainly deserves to be very widely 
known. 
In the course of the discussion Mr. Charles Ball, who has 
worked a large number of these dredgers, mentioned that he had - 
forced sand thus dredged fora distance of 600 yards through 
horizontal pipes, by the mere action of the pump. To prevent 
the silt from settling during its passage along open troughs, he 
had inserted a light’ angle iron in an undulating line along the 
inside of the trough, so as to give the water a continual twisting 
motion as it travelled onwards. The great difficulty was to 
prevent the water from ceasing to flow, either from the sand 
accumulating above the pump, or from old sacks and other 
rubbish choking the nozzle, The former was got over mainly 
by making the discharge-pipe horizontal, and giving it a siphon 
bend, which kept the water always within it, and prevented any 
difficulty in starting the pump; and the latter by making openings 
in the nozzle, just above the grating, which were covered by an 
indiarubber band having slits in it. When the grating got 
choked and a vacuum began to form inside the nozzle, the-e slits 
opened to the pressure, and allowed the water to flow in. 
The third paper was by Mr. E. B. Ellington, on hydraulic 
lifts for pas-engers and goods. The risks which attend the use 
of ordinary chain lifts were minutely described, and also the way 
in which these are removed by the use of direct acting hydraulic 
lifts, in which the cage rests on the top of a column of pressure- 
water, both in ascending and descending, ‘The chief difficulty 
with such lifts is to balance the dead weight of the cage and 
attachments, so as to save the needless expenditure of power in 
raising these each time; and an ingenious arrangement of 
hydraulic cylinders is described, by which this is attained with- 
out the use of counter-weizhts or chains. A table of experi- 
ments on lifts of this and other types is given, which shows the 
efficiency to be very high, ranging from 75 to 80 percent. The 
discussion on this paper was adjourned, for want of time, to the 
next meeting. 
THE CHEMISTRY OF BAST FIBRE* 
[NX a previous paper (see Chem. News, 43, 77, and Chem. Soc. 
Jour. xxxvili, 666) the authors established the following 
points :—The chemical similarity between the non-cellulose con- 
stituents of monocotyledonous and dicotyledonous fibres ; the 
re-olution of the jute fibre by chlorine into cellulose (using this 
word in a general sense), and the chloroderivative of an aromatic 
body, 7{C,,H,,Cl,O9}; all bast fibres examined (flax, hemp, 
manilla, esparto, &c.) yielded a similar body ; the reactions of 
this substance suggested the hypothesis that it was a complicated 
derivative of tetrachlorquinone ; jute fibre was resolved by boil- 
ing dilute hydrochloric or sulphuric acid into a soluble carbo- 
hydrate and an insoluble compound of the aromatic body with 
the more stable form of the cellulose ; dilute nitric acid resolves 
the fibre into cellulose and a ni‘roderivative of the aromatic 
constituents 7 {C,,H3,(NO,)O.3H,}; no constituent of the nature 
of pectose was found, From these facts the authors drew the 
conclusion that jute fibre consists of cellulose intimately asso- 
ciated with a complicated body allied to the quinones, in fact, a 
cellulide after the type of the glucosides, the aromatic body 
being united to cellulose in place of glucose, They also ob- 
served that the chlorinated body, when treated with a solution 
of sodium sulphite, develops a magnificent purple colour; this 
reaction was applied for the detection of bast fibres. In the 
present paper the authors have continued this line of research. 
To the aromatic constituent of the jute fibre the authors assign 
the formula C,,H, :0O,. The resemblance of this formula to 
that of catechin, C,,H,,0,, 3H.O, suggested a comparative 
investigation of the latter substance ; both catechin and catechu- 
Abstract of papers by C. F. Cross and E. J. Bevan at the Chemical 
Society, January 19. 
