Manon 29, 1872. THE BUILDING NEWS. lupe 263
get the better for the purpose, but always with ex-
planatory geometrical elevations. Mr, Sharpe con-
tinued to say that there was another great objec-
tion to presenting a building solely in elevation.
He defied any one, even an architect, to say what
the effect of certain projections would be. He
directed attention to four drawings on the wall, re-
presenting two well-known towers and spires, and
illustrating what was a very common thing in prac-
tice—the structure of an octagon upon a square.
Mr. Sharpe continued: We know very well that
every octagon put upon a square in geometrical ele-
vation presents the same breadth from top to bottom.
The moment you have it in perspective, you see that
the octagon is less than the square, except from
certain points of view ; from the four cardinal points
of view, if you will permit me to call them so,
perhaps you get avery good geometrical elevation,
but from any other point of view, you do not see
that effect. The mode in which the building ought
tobe presented to view is not an exceptional one,
but the ordinary one; that which is usually seen.
The manner in which thelaws of perspective affect
the appearance of octagonal spires and square towers
is well illustrated in the four drawings of the towers
and spires of Ewerby and Threckingham Churches,
of which the left-hand drawing in each case re-
presents the geometrical elevation, and the right-
hand drawing the perspective view. The contrast
is startling; the clumsy predominance of the spire
over the tower in the left-hand drawing in both cases
is as remarkable as the graceful effect of perspective
upon both structures in the right-hand drawings.
Now, will you tellme that the architect designed the
left-hand drawing first, and let the right-hand
one come out asit might? No, he knew very well,
perhaps from previous experiment, what would be the
perspective effect of the building he intended to
present to the public. That is the mode in which
all architects who profess to be artists ought to
study and produce their designs and present them to
the public. Permit me to draw your attention to
another fact, and a very important one. Suppose
for example, the elevation of the west front of
Wells Cathedral and all the statues it contains were
to be drawn as they really are; or, taking a modern
case, that the sculptor of any of our public monu-
ments—that of Nelson, for instance—were to design
and present ts the public his drawing in geometrical
elevation instead of in perspective; why, such a
drawing would be totally repugnant to the ideas of
everybody who saw it, because it would present the
lower part of the figure out of proportion to the
rest; in fact, it would not be foreshortened, as it
would in perspective. I think that we may demand
the same privileges as architects that sculptors have,
and I think we ought to present our designs in the
same way—viz., from a perspective point of view,
and not in elevation, for the one presents distortion,
and the other presents reality. One word more, as
T should fall very short of what I mean without
saying what I am going to say. I protest as
emphatically as any gentleman here will against the
dressing-up of perspective views by means of colour,
by means of accessories of all kinds that do not form
any portion of the architecture of the building. I
protest as emphatically as any one can protest
against that sort of meretricious and adventitious aid
to perspective views, and can only express the hope
that the Institute may come to the decision that all
drawings sent inin competitions should be devoid of
all adventitious ornaments of any kind whatever
except that derived from the introduction of the
human figure, drawn in true proportions, and that
all such drawings should be tinted in one colour
only. '
—_—_<—___
VENTILATION AND PURIFICATION IN
FACTORIES, &c.*
aot previous to the late war, M. Charles de
Frécinet, mining engineer, was charged by the
late Imperial Government with a commission to visit
the most important factories and workshops in
England, France, Germany, and Belgium, and to
report on the means adopted to prevent the ill effects
of the various deleterious agencies on the health of
the operatives. The results of this investigation
were printed in four large volumes, but the very
voluminous nature of the work, and the stirring
events that followed upon its appearance, have caused
it to be but little noticed, except by a few scientific
men. It will, therefore, be useful to note a few of
the observations of M. de Frécinet, and especially of
those which refer to foreign countries,
After speaking of the good effects produced in
Durham by the construction of tall chimney-shafts
for the coke ovens, M. de Frécinet says that in Bel-
ginm all the new coke furnaces are compelled by law
a en ESS eae ee Ye
- From The Society of Arts Journal.
to have chimney-shafts of 45ft. to 60ft. high, in order to ensure the carrying off of the gases. In the wine-making districts of France, it has been found that exhalations from the lime and brick kilns have a most serious effect on the quality of the grapes; the wine extracted from them has an unpleasant taste of soot, and the proprietors of the kilns have often been compelled to pay heavy damages to the wine- growers. The construction of tall chimney-shafts, therefore, became an absolute necessity, and the case of §, Etienne is cited as one in which the mischief caused by the numerous coke furnaces around the town was completely stopped by the adoption of tall shafts. Ventilation by means of fans placed in the build- ings themselves, or applied directly to the engines, is pretty generally adopted in the French white-lead, tobacco, and leather-dressing manufactories, and in woollen and cotton mills. In other cases, water is used to condense injurious vapours; and in the soda works high stone towers are employed to condense the smoke. The dangers which those workmen run who have habitually to make use of quicksilver are too well- known to require description. In the works at S. Gobain, Cirey, and Chauny, the men are not em- ployed more than three days in the week in the silvering of looking-glass, and the windows, which are provided with good ventilators, are kept open whenever possible. The tools, covered with flannel, by means of which the mercury is spread on the tin- foil, have handles 4ft. long; the mercury is kept in hermetically-sealed receptacles, and the cloths through which it is passed, in order to remove impurities, are beaten in well-closed boxes and in the open air. In silvering by means of mereury, by the method of MM. Bonin, of Paris, an admirable method is adopted to get rid of the fumes. Over the fire by which the mercury is driven off in the form of vapour is anopen chimney, covered at the top with a large glass globe, and the workmen are protected by a shield, through which they pass their arms. Some manufactures have not been much benefited by science; for instance, no means have been found of reducing the unhealthiness of the chromate of potash works. At those of M. Clouet, of Havre, most of the workmen are subject to cancer, which attacks the nostrils, and which is produced by the particles of chromate which float in the air. The production of sulphate of quinine is no less danger- ous; it affects in a singular manner those who have to manipulate it. The operation of millstone cutting is extremely unhealthy. The population of La Fertésous-Jouarre, the chief centre of this important trade, is decimated by the introduction into the lungs of the silicious particles which are in suspension in the air, and it is calculated that ten years’ employ- ment in the business generally produces fatal disease. The charcoal dust used in the iron and bronze foundries for covering the moulds is also found very injurious to the health of the men engaged, and in consequence potato flour is now generally used in Paris, in place of charcoal, with good results. In bark grinding and other works, where simple ventilators have generally been used, reservoirs are now added, so that the dust is both withdrawn and collected, and does not contaminate the air. In the cotton mills of M. Fauquet, at Oisel, the principal room, which is nearly 3,000 feet long, and is used both for carding and spinning, is constructed in a special manner, with the triple object of secur- ing uniform temperature, driving out the impure air, and supplying fresh air. In order to prevent the variations of temperature arising from change of weather, the vaulting of the roof was covered with honeycombed work, in the following manner :—A number of glass bottles were arranged upright and in alternating rows, mortar was then poured into the interstices, and, the bottles being removed, left a spongy, porous coating, which was afterwards covered on the top with plaster. By this means a double ceiling was produced, enclosing a stratum of warm air contained in a multitude of cells. Two powerful ventilators in a subterranean gallery carry off the impure air and supply fresh, the circulation of the latter being secured by passages beneath the flooring, having thirty openings into the room. Lastly, a jet of water is used in the fresh-air gallery when additional humidity is requisite. In the tobacco factories, uniformity of temperature is not requisite, and the dust is much less than in cotton and other mills, but there are exhalations from the fermenting tobacco to be removed. In the French Government factories, ventilating fans are used, and eight cubic metres of air per hour are allowed for each workman. The factories are heated with caloriféres, with tall chimney shafts. In some white-lead works, and where lead enamel for telegraphic insulators is ground, the millstones are | enclosed in tight cases, and arein direct communica-
tion with the ventilating fan. In M. Kestner’s fac-
tory at Thann, the rooms in which chlorate of lime
is made have leaden pipes, which carry off the gases
to the main chimney-shaft; a register is opened an
hour or two before the men arrive to their work, a
strong current is established, and the air of the place
completely renewed.
Tn the lead foundry of M. Lepau, at Lille, each
furnace has a eupola which communicates by means
of a flue furnished with a register, with the bottom
of the cinder-hole of the steam-engines. Similar
arrangements are adopted in nearly all the French
factories employing mineral oils and greases, and
where pyroligneous acid and sulphuretted hy-
drogen are produced. The method is considered
applicable to all works where organic substances are
treated; and the economy of combustibles is consider-
able. In some soap works, the boilers are furnished
with iron hoods, which have pipes which conyey the
gases beneath the steam-engine furnace, where they
are dispelled by a jet of steam.
At Aix-la-Chapelle, the Prussian authorities have
strictly prohibited the grinding of needles, except in
shops provided with thorough means of ventilation
and for carrying off the atomsof metal. In some of
the shops at that place, each stone is furnished with
its own ventilator. In the chemical works of M.
Mercks, at Darmstadt, where great quantities of
belladonna are prepared, a large hood connected
with a chimney is brought down over the grinding-
mill, and never allowed to be raised until the
grinding is done and all the dust carried off. In
many other drug works the grinding mills are en-
closed and ventilated in like manner.
In the chemical works of M. Gundelach, at Mann-
heim, the men who repair the leaden chambers for
the manufacture of sulphuric acid and chioride of
lime wear a head-piece, connected by flexible tubes
with an air-pump, asin diving. The same plan is
adopted at Worms and at Heilbronn.
The severity of the Belgian Government in such
matters has caused the manufacturers to adopt
many ingenious devices. In M. De Hemptine’s
works, at Molenbeck, S.-Jean, near Brussels, the
platinum still for the concentration of sulphuric acid
is built into a wall; over the still is a cover, in the
centre of which is the man-hole, which, when the
mill is at work, is closed hermetically by a leaden
plate, and from the space thus formed between this
cover and the top of the still a leaden pipe carries
off the vapours into the main chimney-shaft of the
works.
In the extensive paper-mills of M. Godin, at Huy,
where chlorine gas is used for bleaching the pulp,
the gas is carried off by means of stone channels,
which are in communication with a central chamber
30ft. high, where absorption is effected on a grand
seale.
At Ghent and Dusseldorf, white-lead is groundin
oil or water, in order to prevent the dispersion of
the fine particles. This substance used to be em-
ployed in bleaching lace, but it caused such mortality
amongst the workmen that the Government inter-
dicted it. In the chemical works of M. Zimmer, at
Sachenhausen, near Frankfort, the bark for the pre-
paration of sulphate of quinine is ground in a state
of fermentation in mills hermetically sealed. In
the purification of the sulphate, the evaporating
vats are placed in a special room, and under domes
furnished with special shafts.
At the lucifer-match works of M. De Roubaix,
at Heurixen, near Antwerp, the five buildings in
which the various preparations are made are venti-
lated by means of a great central chimney-shaft,
which receives the gases from the steam furnaces,
and the draught of which is aided, when necessary,
by a special furnace. A spacious subterranean
channel runs round the base of each building, and
terminates in the central shaft. An opening is
made in every part where phosphorus is employed,
with a channel leading to the main one above de-
scribed.
At the woollen works of MM. Hauzein, Gérard,
& Co., of Verviers, the carding machines are situ-
ated in a separate building, provided with ventilating
fans. The wool is placed on a rack, forming one
side of an otherwise closed case; a powerful fan
acts within this enclosure, while a current of hot
air is directed against the walls of the building. By
these simple means, the workpeople are relieved
from all the dust and other matters which would
contaminate the air.
At Ypres, the lime used in the purification of gas,
upon being withdrawn from the purifiers, is imme-
diately mixed with cinders, which destroy the un-
healthy odours, and the mixture is eventually sold
as manure.
After the previous accounts from other countries
of the aid rendered by science to humanity, it is
hard to haye to transcribe the following expressions