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Lippincott's Magazine of Popular Literature and Science, Vol. XVI., December, 1880 online

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two and a half feet the loss is sixty per cent.; and with three and a
half feet it is thirty-four per cent. of that derived from the gas when
burning the full quantity for which the burner is constructed. In some
experiments made upon this matter under the direction of referees
appointed by the London Board of Trade the loss at the other extreme is
given. They report: 'Instead of the gas giving increased light as the
rate of consumption is increased, it will be seen that _in every case_
there is a point beyond which the _light decreases_ relatively to the
proportion of gas consumed. In every case, too, this point lies far
below the maximum of gas-consumption, observing the turning-points in
the case of the different burners.' Again, every burner has a certain
amount of gas which it will consume to the greatest advantage as to both
light and economy; which in a completely-regulated burner is quickly
found, and the delivery fixed by the small tap. When the gas is issuing
from the burner at so low a pressure that the flame is just on the point
of smoking, the maximum effect for the quantity of gas consumed in that
particular burner is attained, because in that case the quantity and
intensity of the light are most advantageously balanced. For the same
reason, the burner best suited for light is one in which the
jet-openings are proportionately large, so as to prevent as much as
possible too great contact with the air in the lower part of the flame.
In case the air-currents disturb the light, it is necessary to turn on a
stronger flow, which secures steadiness, but sets economy at naught."

"It would be a good thing," said the young fellow, interrupting him, "if
some person would invent a burner that should heat the gas before its
discharge. We could then get a perfect combustion of the carbon, and so
greater brilliancy and economy."

"That is a very common error. Mr. Leslie's burner was designed on that
very theory: the result was contrary to expectation."

"What was the form of the burner?" inquired our host.

"Leslie's burner is a form of the argand. The gas, instead of issuing
from holes pierced in a solid ring, is conducted to the flame in
separate small tubes upward of an inch long. Twenty-eight of these tubes
are inserted in a ring two inches in diameter, and converge to one inch
at the ends, where the gas escapes. These tubes become hot very quickly
when the gas is lighted, and it issues at a high temperature. Here is
the result of a test made by Mr. Clegg, and given on page 344 of his
valuable work on coal gas:

COMMON ARGAND, FIFTEEN HOLES.
Consumption per hour in cubic feet:
6 feet, light = 17.4 standard candles.
5 feet, light = 13.64 standard candles

LESLIE'S BURNER, TWENTY-EIGHT HOLES.
6 feet, light = 14.73 standard candles.
5 feet, light = 11.28 standard candles.

"In experimenting with common burners, argand and others, it is found
that, if the aperture in the tip is too small for the orifice in the
body of the burner, the escaping gas is too highly heated and is
consumed too quickly. So with Leslie's burner in an increased degree.
Theories brought to the test of experiment are often disappointing."

The chemist now proceeded to illustrate his harangue with the argand
upon the table, which he lighted and turned on full, without replacing
the chimney. The dull-red flame streamed up to a height of eight inches
or more, waving and smoking slightly. He now turned down the gas and
replaced the chimney, then set the tap at the same angle as before.
"Here," said he, "we have a flame barely four inches high - of brilliant
white - which gives more light than the taller flame did. The cause of
the shortening of the flame is the more rapid combustion of the gas,
owing to the increased draught or air-supply in the chimney. From the
greater intensity of this flame a much larger quantity of light is
produced than by the longer flame. If too tall a chimney is used, the
flame is shortened still more and its brilliancy increased, but not to a
degree sufficient to compensate for the diminished surface. The light,
you are doubtless aware, comes from the incandescence of the carbon,
heated by the union of the hydrogen of the gas with a portion of the
oxygen of the air."

The chemist now read from his manuscript again: "Carburetted hydrogen of
a passably good quality requires two volumes of pure oxygen for its
complete combustion and conversion into carbonic acid and water.
Atmospheric air contains, in its pure state, about twenty per cent. of
oxygen; therefore, one cubic foot of gas requires for its perfect
combustion ten cubic feet of air. If less be admitted to the flame, a
quantity of free carbon will escape, and be deposited in the form of
black smoke. If an excess of air be admitted, we shall find that the
quantity of nitrogen accompanying this excess has a tendency to
extinguish the flame, while it takes no part in the elective affinity
constantly going on between the other elements - namely, hydrogen, oxygen
and the vapor of carbon.

"Again," said he, turning down the gas, "if the flame be reduced to a
consumption of two feet per hour, its light will be equal to that of one
candle only; but on raising the chimney, thus, about half an inch from
the gallery or support the light is greatly increased, or by simply
placing a disk on top of the chimney the light is increased ninefold;
both of which effects seem to result from a diminished current of air,
while at the same time there is an ample supply. Lastly, with the
ordinary glass moon-globe so generally used in dwellings with the
fishtail burner little difference can be perceived between the light
given from the flame by four feet and that from six feet of gas per
hour, in consequence of the strong current of air passing up through the
globe; but if the top of the glass be enclosed by a talc cover having an
orifice in the centre about an inch in diameter, then the conditions of
the burner are completely changed. The light is greatly increased,
because the highest economical advantage is then approached."[2]

"Smoke from the aperture and lamp-black on the cover must result from
such an arrangement," objected the old gentleman.

"There need be very little of either," responded the chemist. "From some
burners there is little light without smoke. A smoky flame may arise
from too much carbon, but the gas companies in this part of the country
are not apt to make their product too rich; and such a condition is not
likely to occur except with vapor-gas when warm weather quickly succeeds
to a cold spell in the winter season. The consumer's immediate remedy in
any case is to use a smaller tip with the fishtail and batwing burners,
and a taller chimney with the argand; which devices will give a quicker
movement to the gas in one case and to the air in the other. The
smoking, however, may be caused by carbonic acid, which checks
combustion. There is always more or less of this in gas, arising from a
partial combustion in the retorts when charging them with coal or while
withdrawing the exhausted charge. But it is only by excessively slow and
careless work that this can happen to a serious extent. Only an expert
can tell when this condition exists, though if the symptoms do not yield
to manipulations of the chimney and tap, it may be suspected. There is
no effective remedy for this adulteration which can be applied by the
consumer except a vigorous complaint against the company which supplies
the stuff.

"There remains one burner or lamp to be mentioned, contrived with
special reference to health," he continued - "the ventilating standard
lamp of Doctor Faraday, used in the House of Lords. In this there is an
outer glass by which the vitiated air passes away through the pipe
communicating with the external air. The lamp is interesting, but there
is a question whether there is any practical advantage in its use.
Rutter's ventilating lamp is of different form, having a globe instead
of an outer cylinder, the gas and air coming in from above. Some of the
best dwellings now being erected in the vicinity of New York are
provided with tin pipes leading from the burners to the open air. In
some the pipe receives the foul air from an open metallic or mineral
shade over the burner; others have a larger pipe enclosing the gas-pipe
for ventilation, the tops of the two pipes (including the burner) being
enclosed by a globe pierced with holes for fresh air. There is said to
result a good ventilation, with economy of gas, an increased steadiness
of the flame and power of light. A better arrangement is a third pipe
enclosing the gas-pipe and enclosed in the ventilating-pipe, opening to
the air, instead of the holes in the globe, which in this case should be
air-tight. This plan is said to have reached its perfection when the
three pipes are filled with wire gauze to some extent. This, being
heated by the escape of hot gases in the ventilating-pipe, sends both
the air and the gas to the flame already highly heated. The result is
said to be admirable as regards ventilation, steadiness and power of the
light and economy of gas.

"With these lamps the pressure of the gas-current is of great
importance; and I now turn to that subject. It is a general complaint in
buildings whose rooms are high that the flow of gas on the lower floor
is deficient, while on the upper floors there is a greater supply than
is necessary. This inconvenience arises from the upper stories being
subjected to less atmospheric pressure than the lower, every rise of ten
feet making a difference in the pressure of about one-tenth of an inch
of water; and, consequently, a column of gas acquires that amount of
pressure additional. The following table, recording an experiment of Mr.
Richards, will show the result in respect to light:

Gas issuing from the burner at a pressure of -
1/10 inch of water gave the light of 12 candles,
5/10 " " " " " " " 6 "
10/10 " " " " " " " 2 "
40/10 " " " " no appreciable light.

Suppose a building of six floors is supplied from the gas-mains at a
pressure of six-tenths, and that the difference of altitude between the
highest and lowest light is equal to fifty feet: the gas in the highest
or sixth floor will issue from the burners at a pressure of
eleven-tenths; the fifth floor, at ten-tenths; and so on. In order to
secure an entirely equable flow and economical light a regulator is
necessary on each floor above the first. The gas companies are
frequently obliged to supply mills at a much greater pressure than is
stated above as necessary, in order that the ground floors may have
sufficient light."

"How about incorrect meters?" asked the traveller.

"Little need be said of them, as they fall within the domain of the
companies and the public inspector of gas. Under favorable conditions
gas-meters will remain in order for ten years or more; and when they
become defective they as often favor the consumer, probably, as they do
the gas company. Their defects do not often occasion inconvenience; and
when they once get out of order they run so wild that their condition is
soon detected, when the errors in previous bills should be corrected by
estimate of other seasons."

"You haven't mentioned the apparatus (carburetters) for increasing the
richness of the gas, which can be applied by the consumer upon his own
premises," said the old gentleman.

"There is little need. The burners should be adjusted to the quality of
gas furnished. If there were any real gain in this method of enrichment,
the gas companies are the parties who could make the most of it: indeed,
many of them do to such an extent as can be made profitable. But
whenever the temperature of the atmosphere falls, the matter added to
the gas is deposited in the pipes, sometimes choking them entirely at
the angles. No: arrange your burners and regulators to suit the gas that
is furnished, demand of the company that it fulfil the law and the
contract in regard to the quality of the gas, and give all gas-improving
machines the go-by.[3]

"Light having, perhaps, been sufficiently considered for the present
needs, we have now to note the effects of the combustion of gas upon the
atmosphere, and through this upon the furnishing of rooms and the health
of the persons living therein," said the chemist, again taking up his
manuscript. "The usual products from the combustion of common
illuminating gas are carbonic acid, sulphuric acid, ammonia and
water-vapor. Every burner consuming five cubic feet of gas per hour
spoils as much air as two full-grown men: it is therefore evident that
the air of a room thus lighted would soon become vitiated if an ample
supply of fresh air were not frequently admitted.

"Remember," said he, looking up from the paper, "that nearly the same
effects proceed from the combustion of candles and lamps of every kind
when a sufficient number of these are burned to give an equal amount of
light. Carbonic acid is easily got rid of, for the rooms where gas is
burned usually have sufficient ventilation near the floor by means of a
register, or even the slight apertures under the doors - together with
their frequent opening - to carry off the small quantity emitted by one
or two burners. But there are other gases which must have vent at the
upper part of the room, while fresh air should be admitted to supply the
place of that which is chemically changed."

Returning to his manuscript, he continued: "The burners which give the
least light, burning instead with a low, blue flame, form the most
carbonic acid and free the most nitrogen. Such are all the burners for
heat rather than light. But the formation of sulphuric acid gas may be
the same in each. In the yellow flame the carbon particles escape to
darken the light colors of the room, not being heated sufficiently to
combine with the oxygen. This product of the combustion of gas (free
carbon) might be regarded as rather wholesome than otherwise (as its
nature is that of an absorbent) were it not the worst kind of dust to
breathe - in fact, clogging the lungs to suffocation. In vapor gas - made
at low heat - the carbon is in a large degree only mechanically mixed
with the hydrogen, and is liable, especially in cold weather, to be
deposited in the pipes. This leaves only a very poor, thin gas, mainly
hydrogen, which burns with a pale blue flame, as seen in cold spells in
winter. High heats and short charges in the retorts of the manufactory
give a purer gas and a larger production. Gas made at high heat will
reach the consumer in any weather very nearly as rich as when it leaves
the gas-holder; for, thus made, the hydrogen and carbon are chemically
combined, instead of the hydrogen merely bearing a quantity of
carbon-vapor mechanically mixed and liable to deposit with every
reduction of temperature. To relieve the atmosphere of the gases and
vapors proceeding from combustion is, of course, the purpose of
ventilation. The sulphuric acid gas and ammonia will be largely in
combination with the water-vapor, which also proceeds from combustion,
so that all will be got rid of together. The vaporization of libraries
to counteract the excessive dryness (or drying, rather) which causes
leather bindings to shrink and to break at the joints, would be of
doubtful utility, since it might only serve to carry into the porous
leather still more of the gases just mentioned. The action of both
sulphuric acid and ammonia is, undoubtedly, to destroy the fibre of
leather, so that it crumbles to meal or falls apart in flakes.

"In a very interesting paper read by Professor William R. Nichols of the
Massachusetts Institute of Technology before the American Association of
Science at its Saratoga meeting in 1879, the results of many analyses of
leather bindings were given, showing the presence of the above-named
substances in old bindings in many times greater quantity than in new.
Still, their presence did not prove them to be the cause of the decay;
and Professor Nichols proposes to ascertain the fact by experiments
requiring some years for demonstration.

"In the hope of deciding the question with reasonable certainty at once,
I have made careful examinations of the books in the three largest
libraries of Boston and Cambridge, each differing from the others in age
and atmosphere. The bindings of the volumes examined bore their own
record in dates and ownership, by which the conditions of their
atmosphere in respect to gas and (approximately) to heat were made
known for periods varying from current time to over two hundred years.
In the Public Library the combined influences of gas, heat and effluvium
have wrought upon the leather until many covers were ready to drop to
pieces at a touch. The binding showed no more shrinkage than in the
other libraries, but in proportion to the time the books had been upon
the shelves the decay of the leather was about the same as in the
Athenæum. I am informed that many of the most decayed have from time to
time been rebound, so that a full comparison cannot be made between this
and the others. In the Athenæum less gas has been used, and there is
very little effluvium, but the mealy texture of the leather is general
among the older tenants of the shelves. Numbers of volumes in the
galleries were losing their backs, which were more or less broken off at
the joints from the shrinkage and brittleness of the leather. The plan
has been proposed of introducing the vapor of water to counteract the
effects of dryness upon the bindings. In this library the atmosphere has
the usual humidity of that out of doors, being warmed by bringing the
outer air in over pipes conveying hot water, while the other libraries
have the higher heat of steam-pipes. If, therefore, its atmosphere
differs from that of the other libraries in respect to moisture, the
variation is in the direction of greater humidity, without any
corresponding effect on the preservation of bindings. In fact, proper
ventilation and low shelves seem to be the true remedies for these
evils, or, rather, the best means of amelioration, since there is no
complete antidote to the decay common to all material things. The last
condition involves the disuse of galleries and of rooms upon more than
one flat, unless the atmosphere in the upper portions of the lower rooms
be shut off from the higher, as it should be. Another precaution which
might be taken with advantage is to use the higher shelves for cloth
bindings.

"In the Harvard College Library no gas has ever been used, nor any other
artificial illuminator to much extent. Neither had any large number of
the volumes been exposed to the products of gas-combustion, except for
a brief time before they were placed here. The bindings in this library
showed very little crumbling, but many covers were breaking at the
joints from the shrinking which arises from excessive dryness. In common
with many other substances, leather yields moisture to the air much more
readily than it receives it from that medium. Cloth bindings showed no
decay at all here - very little in any of the libraries, except in the
loss of color. It should be stated that the volumes which I examined at
Harvard College were generally older than those inspected in the other
libraries. There are parchment bindings in each of the libraries
hundreds of years old, apparently just as perfect in texture as when
first placed upon the shelves of the original owner. The parchment was
often worn through at the angles, but there was no breakage from
shrinking, the material having been shrunken as much as possible when
prepared from the skin. At Harvard College I examined an embossed calf
binding stretched on wooden sides which was above a hundred years old.
It was in almost perfect preservation, and not much shrunken. This
volume, being very large, was on a shelf next the ground floor - a
position which it had probably held ever since the erection of the
building.

"Professor Nichols does not mention morocco in his tables of analyses.
Indeed, morocco was so little used for bookbindings until within about
thirty years that it affords a less ample field for investigation than
any other of the leathers now in common use. My attention was therefore
directed specially to this material, of which I found some specimens
having a record of nearly fifty years. My observation was, that in all
the libraries these were less affected by decay, in proportion to their
age, than other leathers. In Harvard College Library the best Turkey
morocco, with forty years of exposure, showed no injury except from
chafing. The outer integument was often worn away, exposing the texture
of the skin, which was still of strong fibre. In the Athenæum, on the
contrary, many of the moroccos showed the same decay as the calf,
russia and sheep. There was, however, a wide difference in the condition
of moroccos of the same age - some showing as much decay as the calf,
while others had scarcely any of the disintegration common to the older
calf bindings. The same might, indeed, be said of all leathers, those
tanned by the quick modern methods, with much more acid than is used in
old processes, in which time is a large factor, showing always a more
rapid deterioration. But, the methods being the same, morocco, the
oiliest of the common leathers and the one having the firmest cuticle,
endures the best.

"The order of endurance of leather (as observed by librarians) against
atmospheric effects is as follows, descending from the first to the last
in order: Parchment, light-colored morocco, sheep, russia, calf. Cloth
wears out quickly by use, but appears - the linen especially - to be
affected by the atmosphere only in loss of color. These observations all
refer to the ordinary humidity of the air in frequented rooms.

"This, then, is the result of my inquiries: I found the shrinking and
breaking resulting from heat much the same in all the libraries, but
most in that where the heating is from the outer air brought in over
hot-water pipes, the two other libraries examined being warmed by
steam-pipes having a higher temperature. I found the mealy structure - or
instead thereof flakiness - to prevail most in the Athenæum, next in the
Public Library: in the latter, however, many volumes have been rebound,
thus raising the average of condition. In the Harvard College Library no
gas - in fact, little if any artificial light - is used, and here, too,
the mealy structure and disintegration are mostly absent. I conclude,
therefore, from these limited observations, that heat is responsible for
a large part of the damage to leather bindings, its effects being
evidently supplemented and hastened by gas-combustion.

"The ventilating lamps before described, though rather cumbrous to eyes
accustomed to the small and simple apparatus commonly used, might prove
valuable in rooms containing fabrics liable; to be injured by the gases
from open burners."

As the chemist concluded his reading the traveller remarked to the
somewhat weary listeners, "You now see the vast amount of study and care
required to use gas with economy and safety. I could not have argued the
cause of a new, clean, gasless and vaporless light like electricity any
better myself."

"It will be found," responded the chemist, "that there are more troubles
and dangers connected with the electric light - besides the larger
expense - than are thought of now."

"That is so!" ejaculated the young fellow.

"At any rate," said the old gentleman, "gas stock won't go lower for
twenty years than it has been this winter."

"You are all wedded to your idols," was the final protest of the
traveller.

"I wish I was," murmured the young fellow, with a side-glance at his
fair neighbor, who immediately removed to another part of the room.

GEORGE J. VARNEY.




THE "_???? ??G?????_ IN SHAKESPEARE.


When we examine the vocabulary of Shakespeare, what first strikes us is
its copiousness. His characters are countless, and each one speaks his
own dialect. His little fishes never talk like whales, nor do his whales
talk like little fishes. Those curious in such matters have detected in
his works quotations from seven foreign tongues, and those from Latin
alone amount to one hundred and thirty-two.

Our first impression, that the Shakespearian variety of words is
multitudinous, is confirmed by statistics. Mrs. Cowden Clarke has
counted those words one by one, and ascertained their sum to be not less
than fifteen thousand. The total vocabulary of Milton's poetical remains


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Online LibraryVariousLippincott's Magazine of Popular Literature and Science, Vol. XVI., December, 1880 → online text (page 14 of 20)