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SCIENTIFIC AMERICAN SUPPLEMENT NO. 360 - NOVEMBER 25 - 1882
SCIENTIFIC AMERICAN SUPPLEMENT NO. 360 - NOVEMBER 25 - 1882 VARIOUS Produced by Olaf Voss Don Kretz Juliet Sutherland
Charles Franks and the Online Distributed Proofreading Team
[Illustration]
SCIENTIFIC AMERICAN SUPPLEMENT NO. 360
NEW YORK NOVEMBER 25 1882
Scientific American Supplement. Vol. XIV No. 360.
Scientific American established 1845
Scientific American Supplement $5 a year.
Scientific American and Supplement $7 a year.
* * * * *
TABLE OF CONTENTS.
I. ENGINEERING AND MECHANICS.--Soaking Pits for Steel Ingots.
--On the successful rolling of steel ingots with their own
initial heat by means of the soaking pit process. By JOHN GJERS.
6 figures.--Gjers' soaking pits for steel ingots.
Tempering by compression.--L. Clemandot's process.
Economical Steam Power. By WILLIAM BARNET LE VAN.
Mississippi River Improvements near St. Louis Mo.
Bunte's Burette for the Analysis of Furnace Gases. 2 figures.
The "Universal" Gas Engine. 8 figures.--Improved gas engine.
Gas Furnace for Baking Refractory Products. 1 figure.
The Efficiency of Fans. 5 figures.
Machine for Compressing Coal Refuse into Fuel. 1 figure.--
Bilan's machine.
Hank Sizing and Wringing Machine. 1 figure.
Improved Coke Breaker. 2 figures.
Improvements in Printing Machinery. 2 figures.
II. TECHNOLOGY AND CHEMISTRY.--Apparatus for Obtaining
Pure Water for Photographic Use. 3 figures.
Black Phosphorus.--By P THENARD.
Composition of Steep Water
Schreiber's Apparatus for Revivifying Bone Black. 5 figures.--
Plant: elevation and plan.--Views of elevation.--Continuous
furnace.
Soap and its Manufacture from a Consumer's Point of View.
(Continued from SUPPLEMENT No. 330).
Cotton seed Oil.--By S. S. BRADFORD.
On some Apparatus that Permit of Entering Flames.--Chevalier
Aldini's wire gauze and asbestos protectors.--Brewster's account
of test experiments.
III. ELECTRICITY LIGHT. ETC.--On a New Arc Electric Lamp.
By W. H. PREECE. 6 figures--The Abdank system.--The lamp.--
The Electro-magnet.--The Cut-off.--The electrical arrangement.
Utilization of Solar Heat.
IV. NATURAL HISTORY.--The Ocellated Pheasant. 1 figure.
The Maidenhair Tree in the Gardens at Broadlands Hants
England. 1 figure.
The Woods of America.--The Jessup collection in the American
Museum of Natural History Central Park and the characteristics
of the specimens.
V. AGRICULTURE ETC.--An Industrial Revolution.--Increase in
the number of farms.
A Farmer's Lime Kiln. 3 figures.
The Manufacture of Apple Jelly.
Improved Grape Bags. 4 figures.
VI. ARCHITECTURE ETC.--The Building Stone Supply.--Granite
and its sources.--Sandstone.--Blue and gray limestone.--Marble.--
Slate.--Other stones.--A valuable summary of the sources and uses
of quarry products.
VII. ASTRONOMY. ETC.--How to Establish a True Meridian. By
Prof. L. M. HAUPT.--Introduction.--Definitions.--To find the
azemuth of Polaris.--Applications etc.
VIII. MISCELLANEOUS.--A Characteristic Mining "Rush."--The
Prospective Mining Center of Southern New Mexico.
The Food and Energy of Man. By Prof. DE CHAUMONT.--Original
food of man.--Function of food.--Classes of alimentary
substances.--Quantity of food.--Importance of varied diet.
Rattlesnake Poison.--Its Antidotes. By H. H. CROFT.
The Chinese Sign Manual.--The ethnic bearing of skin furrows
on the hand.
Lucidity.--Matthew Arnold's remarks at the reopening of the
Liverpool University College and School of Medicine.
* * * * *
SOAKING PITS FOR STEEL INGOTS.
ON THE SUCCESSFUL ROLLING OF STEEL INGOTS WITH THEIR OWN INITIAL HEAT BY
MEANS OF THE SOAKING PIT PROCESS.
By Mr. JOHN GJERS Middlesbrough.
[Footnote: Paper read before the Iron and Steel Institute at Vienna.]
When Sir Henry Bessemer in 1856 made public his great invention and
announced to the world that he was able to produce malleable steel from
cast iron without the expenditure of any fuel except that which already
existed in the fluid metal imparted to it in the blast furnace his
statement was received with doubt and surprise. If he at that time had
been able to add that it was also possible to roll such steel into a
finished bar with no further expenditure of fuel then undoubtedly the
surprise would have been much greater.
Even this however has come to pass; and the author of this paper
is now pleased to be able to inform this meeting that it is not only
possible but that it is extremely easy and practical by the means to
be described to roll a steel ingot into say a bloom a rail or other
finished article with its own initial heat without the aid of the
hitherto universally adopted heating furnace.
It is well understood that in the fluid steel poured into the mould
there is a larger store of heat than is required for the purpose
of rolling or hammering. Not only is there the mere apparent high
temperature of fluid steel but there is the store of latent heat in
this fluid metal which is given out when solidification takes place.
It has no doubt suggested itself to many that this heat of the ingot
ought to be utilized and as a matter of fact there have been at
various times and in different places attempts made to do so; but
hitherto all such attempts have proved failures and a kind of settled
conviction has been established in the steel trade that the theory could
not possibly be carried out in practice.
The difficulty arose from the fact that a steel ingot when newly
stripped is far too hot in the interior for the purpose of rolling and
if it be kept long enough for the interior to become in a fit state
then the exterior gets far too cold to enable it to be rolled
successfully. It has been attempted to overcome this difficulty
by putting the hot ingots under shields or hoods lined with
non-heat-conducting material and to bury them in non-heat-conducting
material in a pulverized state for the purpose of retaining and
equalizing the heat; but all these attempts have proved futile in
practice and the fact remains that the universal practice in steel
works at the present day all over the world is to employ a heating
furnace of some description requiring fuel.
The author introduced his new mode of treating ingots at the Darlington
Steel and Iron Company's Works in Darlington early in June this year
and they are now blooming the whole of their make about 125 tons a
shift or about 300 ingots every twelve hours by such means.
The machinery at Darlington is not adapted for rolling off in one heat;
nevertheless they have rolled off direct from the ingot treated in the
"soaking pits" a considerable number of double-head rails; and the
experience so gained proves conclusively that with proper machinery
there will be no difficulty in doing so regularly. The quality of the
rails so rolled off has been everything that could be desired; and as
many of the defects in rails originate in the heating furnace the
author ventures to predict that even in this respect the new process
will stand the test.
Many eminently practical men have witnessed the operation at Darlington
and they one and all have expressed their great surprise at the result
and at the simple and original means by which it is accomplished.
The process is in course of adoption in several works both in England
and abroad and the author hopes that by the time this paper is being
read there may be some who will from personal experience be able to
testify to the practicability and economy of the process which is
carried out in the manner now to be described.
A number of upright pits (the number say of the ingots in a cast) are
built in a mass of brickwork sunk in the ground below the level of the
floor such pits in cross-section being made slightly larger than that
of the ingot just enough to allow for any fins at the bottom and
somewhat deeper than the longest ingot likely to be used. In practice
the cross section of the pit is made about 3 in. larger than the large
end of the ingot and the top of the ingot may be anything from 6 in. to
18 in. below the top of the pit. These pits are commanded by an ingot
crane by preference so placed in relation to the blooming mill that the
crane also commands the live rollers of the mill.
Each pit is covered with a separate lid at the floor level and after
having been well dried and brought to a red heat by the insertion of hot
ingots they are ready for operation.
As soon as the ingots are stripped (and they should be stripped as early
as practicable) they are transferred one by one and placed separately
by means of the crane into these previously heated pits (which the
author calls "soaking pits") and forthwith covered over with the lid
which practically excludes the air. In these pits thus covered the
ingots are allowed to stand and soak; that is the excessive molten
heat of the interior and any additional heat rendered sensible during
complete solidification but which was latent at the time of placing
the ingots into the pit becomes uniformly distributed or nearly so
throughout the metallic mass. No or comparatively little heat being
able to escape as the ingot is surrounded by brick walls as hot as
itself it follows that the surface heat of the ingot is greatly
increased; and after the space of from twenty to thirty minutes
according to circumstances the ingot is lifted out of the pit
apparently much hotter than it went in and is now swung round to the
rolls by means of the crane in a perfect state of heat for rolling
with this additional advantage to the mill over an ingot heated in an
ordinary furnace from a comparatively cold that it is always certain to
be at least as hot in the center as it is on the surface.
[Illustration: Fig. 2]
Every ingot when cast contains within itself a considerably larger
store of heat than is necessary for the rolling operation. Some of this
heat is of course lost by passing into the mould some is lost by
radiation before the ingot enters into the soaking pit and some is lost
after it enters by being conducted away by the brickwork; but in the
ordinary course of working when there is no undue loss of time in
transferring the ingots after allowing for this loss there remains a
surplus which goes into the brickwork of the soaking pits so that this
surplus of heat from successive ingots tends continually to keep the
pits at the intense heat of the ingot itself. Thus occasionally it
happens that inadvertently an ingot is delayed so long on its way to the
pit as to arrive there somewhat short of heat its temperature will be
raised by heat from the walls of the pit itself; the refractory mass
wherein the pit is formed in fact acting as an accumulator of heat
giving and taking heat as required to carry on the operation in a
continuous and practical manner.
[Illustration: GJERS' SOAKING PITS FOR STEEL INGOTS.]
During the soaking operation a quantity of gas exudes from the ingot and
fills the pit thus entirely excluding atmospheric air from entering;
this is seen escaping round the lid and when the lid is removed
combustion takes place.
It will be seen by analyses given hereinafter that this gas is entirely
composed of hydrogen nitrogen and carbonic oxide so that the ingots
soak in a perfectly non-oxidizing medium. Hence loss of steel by
oxidation does not take place and consequently the great loss of
yield which always occurs in the ordinary heating furnace is entirely
obviated.
The author does not think it necessary to dilate upon the economical
advantages of his process as they are apparent to every practical man
connected with the manufacture of steel.
The operation of steel making on a large scale will by this process be
very much simplified. It will help to dispense with a large number of
men some of them highly paid directly and indirectly connected with
the heating department; it will do away with costly heating furnaces and
gas generators and their costly maintenance; it will save all the coal
used in heating; and what is perhaps of still more importance it will
save the loss in yield of steel; and there will be no more steel spoiled
by overheating in the furnaces.
The process has been in operation too short a time to give precise
and reliable figures but it is hoped that by the next meeting of the
Institute these will be forthcoming from various quarters.
Referring to the illustrations annexed Fig. 1 shows sectional
elevation and Fig. 2 plan of a set of eight soaking pits (marked
A). These pits are built in a mass of brickwork B on a concrete
foundation C; the ingots D standing upright in the pits. The pits are
lined with firebrick lumps 6 in. thick forming an independent lining
E which at any time can be readily renewed. F is a cast iron plate
made to take in four pits and dropped loosely within the large plate
G which surrounds the pits. H is the cover with a firebrick lining;
and I is a false cover of firebrick 1 in. smaller than the cross
section of the pit put in to rest on the top of the ingot. This false
cover need not necessarily be used but is useful to keep the extreme
top of the ingot extra hot. J is the bottom of the pit composed of
broken brick and silver sand forming a good hard bottom at any desired
level.
Figs. 4 and 5 show outline plan of two sets of soaking pits K K eight
each placed under a 25 ft. sweep crane L. This crane if a good one
could handle any ordinary make--up to 2000 tons per week and ought to
have hydraulic racking out and swinging round gear. This crane places
the ingots into the pits and when they are ready picks them out and
swings them round to blooming mill M. With such a crane four men and a
boy at the handles are able to pass the whole of that make through the
pits. The author recommends two sets of pits as shown although one set
of eight pits is quite able to deal with any ordinary output from one
Bessemer pit.
In case of an extraordinarily large output the author recommends a
second crane F for the purpose of placing the ingots in the pits
only the crane L being entirely used for picking the ingots out
and swinging them round to the live rollers of the mill. The relative
position of the cranes soaking pits and blooming mill may of course be
variously arranged according to circumstances and the soaking pits may
be arranged in single or more rows or concentrically with the crane at
pleasure.
Figs. 4 and 5 also show outline plan and elevation of a Bessemer plant
conveniently arranged for working on the soaking pit system. A A are
the converters with a transfer crane B. C is the casting pit with
its crane D. E E are the two ingot cranes. F is a leading crane which
transfers the ingots from the ingot cranes to the soaking pits K K
commanded by the crane L which transfers the prepared ingots to the
mill M. as before described.
* * * * *
TEMPERING BY COMPRESSION.
L. Clemandot has devised a new method of treating metals especially
steel which consists in heating to a cherry red compressing strongly
and keeping up the pressure until the metal is completely cooled. The
results are so much like those of tempering that he calls his process
tempering by compression. The compressed metal becomes exceedingly hard
acquiring a molecular contraction and a fineness of grain such that
polishing gives it the appearance of polished nickel. Compressed steel
like tempered steel acquires the coercitive force which enables it to
absorb magnetism. This property should be studied in connection with
its durability; experiments have already shown that there is no loss of
magnetism at the expiration of three months. This compression has no
analogue but tempering. Hammering and hardening modify the molecular
state of metals especially when they are practiced upon metal that is
nearly cold but the effect of hydraulic pressure is much greater.
The phenomena which are produced in both methods of tempering may be
interpreted in different ways but it seems likely that there is a
molecular approximation an amorphism from which results the homogeneity
that is due to the absence of crystallization. Being an operation which
can be measured it may be graduated and kept within limits which are
prescribed in advance; directions may be given to temper at a
specified pressure as readily as to work under a given pressure of
steam.--_Chron. Industr_.
* * * * *
ECONOMICAL STEAM POWER.
[Footnote: A paper read by title at a recent stated meeting of the
Franklin Institute]
By WILLIAM BARNET LE VAN.
The most economical application of steam power can be realized only by
a judicious arrangement of the plant: namely the engines boilers and
their accessories for transmission.
This may appear a somewhat broad assertion; but it is nevertheless one
which is amply justified by facts open to the consideration of all those
who choose to seek for them.
While it is true that occasionally a factory mill or a water-works
may be found in which the whole arrangements have been planned by a
competent engineer yet such is the exception and not the rule and such
examples form but a very small percentage of the whole.
The fact is that but few users of steam power are aware of the numerous
items which compose the cost of economical steam power while a yet
smaller number give sufficient consideration to the relations which
these items bear to each other or the manner in which the economy of
any given boiler or engine is affected by the circumstances under which
it is run.
A large number of persons--and they are those who should know better
too--take for granted that a boiler or engine which is good for one
situation is good for all; a greater error than such an assumption can
scarcely be imagined.
It is true that there are certain classes of engines and boilers which
may be relied upon to give moderately good results in almost any
situation--and the best results should _always_ be desired in
arrangement of a mill--there are a considerable number of details which
must be taken into consideration in making a choice of boilers and
engines.
Take the case of a mill in which it has been supposed that the motive
power could be best exerted by a single engine. The question now is
whether or not it would be best to divide the total power required among
a number of engines.
_First_.--A division of the motive power presents the following
advantages namely a saving of expense on lines of shafting of large
diameter.
_Second_.--Dispensing with the large driving belt or gearing the first
named of which in one instance under the writer's observation absorbed
_sixty horse-power_ out of about 480 or about _seven per cent_.
_Third_.--The general convenience of subdividing the work to be done
so that in case of a stoppage of one portion of the work by reason of
a loose coupling or the changing of a pulley etc. that portion only
would need to be stopped.
This last is of itself a most important point and demands careful
consideration.
For example I was at a mill a short time ago when the governor belt
broke. The result was a stoppage of the whole mill. Had the motive power
of this mill been subdivided into a number of small engines only one
department would have been stopped. During the stoppage in this case
the windows of the mill were a sea of heads of men and women (the
operatives) and considerable excitement was caused by the violent
blowing off of steam from the safety-valves due to the stoppage of the
steam supply to the engine; and this excitement continued until the
cause of the stoppage was understood. Had the power in this mill been
subdivided the stoppage of one of a number of engines would scarcely
have been noticed and the blowing off of surplus steam would not have
occurred.
In building a mill the first item to be considered is the interest on
the first cost of the engine boilers etc. This item can be subdivided
with advantage into the amounts of interest on the respective costs of
_First_. The engine or engines;
_Second_ The boiler or boilers;
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Unpublished Work 
