IMPROVEMENTS IN THE MANUFACTURE OF SOFT STEEL OR INGOT IRON, AND IN THE APPLICATION OF THE SAME TO VARIOUS TISEFIT. PURPOSES
Year: 1877

page_text: LETTERS PATENT to William Harvey, Ernest William Harvey, and Alfred
Harvey, of Azoff Villa, North Woolwich, in the County of Essex, Stoel Manu-
facturers, for the Invention of "IMPROVEMENTS IN THE MANUFACTURE OF SOFT
STEEL OR INGOT IRON, AND IN THE APPLICATION OF THE SAME TO VARIOUS
TISEFIT. PURPOSES"
Sealed the 28th March 1877, and dated the 29th January 1877.
PROVISIONAL SPECIFICATION left by the said William Harvey, Ernest
William Hai vey, and Alfred Harvey at the Office of the Commissioners of
Patents on the 29th January 1877
WILLIAM HARVEY, ERNEST WILLIAM HARVEY, and ALFRED HARVEY, of Azoff
Villa, North Woolwich, in the County of Essex, Steel Manufacturers "IMPROVE-
MENTS IN THE MANUFACTURE OF SOFT STEEL OR INGOT IRON, AND IN THE APPLI-
CATION OF THE SAME TO VARIOUS USEFUL PURPOSES"
Our said Invention relates to a process for the manufacture of so called "soft
steel" or "ingot iron" containing as low a per-centage of carbon as 10, or possibly
lower, or, say, containing an amount of carbon ranging from 18 to 10, that is to say,
a soft steel can be made at any notice containing any desued amount of carbon
within the range mentioned Such soft steel made in the manner herein-after
described is especially suitable for wire ropes, telegraph wies (where very low
electrical resistance is required), cable wire, and wire of various kinds which have
to stand great elongation, twist, breaking strains, or other tests
Also for engine
and other forgings, nail making, plates, sheets, hoops, and every purpose where
metal is requued superior to charcoal iron, and where greater tensile strength,
ductility, and toughness are required than can be obtained from the best wrought
iron worked in the ordinary way
The furnace preferred for this manufacture is the well known so called "Siemen's
regenerative" open hearth steel melting furnace which is heated by coal gas and
atmospheric air, or other regenerative gas or reverberatory flat bottomed furnace
may be substituted capable of supplying a heat sufficient to melt wrought iron and
keep the said wrought on in a fluid or molten state for some time
A tap hole is provided at the back of the furnace through which the finished

page_text: That
heat while still on the banks without being pushed into the bath of metal
part however which is charged much above the level of the metal may with
advantage be turned in when at a good white heat, in order to save waste by
oxidation The object of this mode of charging the wrought iron is to prevent the
cooling of the molten metal, which would probably result if the charges were
introduced without previous heating, thereby mcuing the 1sk of portions assuming
a pasty condition instead of being uniformly thin and well melted
fuinace howover be working very hot some of the wrought non may be turned in
with advantage when at a good heat During this melting in of the wrought non
the flame should be kept bordering on a non-oxidising quality
The object of charging the wrought non at this period is as follows
"
-
Should the
1st By running it in in the manner described it liquifies and renders very thin
the thick scum or too silicious slag which accumulates on the surface of the molten
pig iron after being nearly decai bulized by the oic, as is the case in working the
so-called "pig and oio process, thereby preventing the heat (gas and air) from
penetrating through the metal, and so retarding the decarbonizing effect of the
oxygen contained in the flame, and increasing the liability of the said metal
assuming a pasty condition and sinking to the bottom by reason of the deficiency of
heat, but after the wrought non is iun in, the slag being in a very liquid state,
allows the heat and flame to penetrate perfectly, thereby preventing the metal from
sinking to the bottom
2nd Owing to the wrought iron containing but little carbon it is found that
when the whole of it is run in in the manner described the said wrought on by
its diluting action, and the oxygen in the flame by its decarburizing action (during
the time the wrought on was melting) will have reduced the carbon contained in
the metal to not more than 14 or 15, and sometimes even lower, thus reducing the
carbon much quicker than by working with one for the same object, as the time
required for the melting in of the wrought on does not exceed one and a half
hours
When the whole of this wrought on has been melted and turned well in the
bath of inetala 1abble is inserted to insure a thorough admixture of the wrought
11on with the other metal A piece of one should now be thrown into the bath,
and if after a minute or two the one floats on the surface, and there appears to be
no action between the metal and ore, or the ore is only reduced with difficulty,
this is an indication that nearly the whole of the carbon lins been practically
elliminated, that is to say, that the carbon contained in the metal has become so low
that neither the ore nor the oxygen of the flame has any "buining" or taking
out" action on the carbon that remains, but if the ore disappears after 2 o1 3
minutes this is an indication that a little more oie is required, which is accordingly
thrown in at intervals till there is no action, as explained When this is the case
no more ore is required, but a full heat is kept on for 15 or 20 minutes, so that the
oxygen in the flame may possibly burn out a little more of the carbon.
The wrought iron for this stage may consist of the following
-
"
For No 1 quality (herein-before referred to) Hammered slabs, blooms, or wire.
puddled or made from hematite, pig, or equivalent (to secure the punity), charcoal
iron scrap, bundled up or other bais, blooms, or scrap which contains very little or
only a trace of impunity, the carbon however is immaterial
For No 2 quality Old bai non, T 11on, angle iron, and merchant iron, scrap or
old wire of any description, also soft steel scrap, ingot ends, plate cuttings, and the
like
For No 3 quality Old uon rails, bars, wrought scrap of any description, plate
cuttings, and the like
If pig iron only be used, as is the custom at some works, or if instead of wrought
iron steel scrap be added to pig iron, and the whole decarburized, either by the
oxygen in the flame or by the ore, the carbon by working in the said one may be
reduced when the ore has no further action on the metal (as explained) to nearly
the same figure as previously specified, namely, 13 or higher, which cannot further

page_text: be reduced by the oxygen of the flame or by the oro, hence more wrought iron of
a particular kind can by our Invention be worked in the bath of metal with advan-
tage to reduce the carbon to a lower figure before charging with feiro-manganese
A
When nearly the whole of the carbon has been eliminated the surface of the
bath of inetal will show numerous thin and very liquid "pools," like water, and on
which the heat seems to have greater effect than on the remaining surface
sample now taken out will be found to contain about 12 per cent of carbon When
this point is reached wrought on ranging from 10 to 30 per cent or higher (of the
total charge exclusive of ore) is introduced, according to the carbon required in the
finished metal, that is to say, if soft steel containing 10 per cent of carbon is
required, then from 23 to 30 per cent of wrought iron must be added
If 15 per
cent of carbon is required, 17 per cent of wrought iron must be charged, and so on,
the quantity charged being in proportion to the carbon required Such wrought
iron should be put in in quantities of 5 01 6 cwt or more at a time on each bank,
and allowed to melt in entirely by the heat of the furnace without pushing in any
part thereof, except that which is furthest away from the metal, which should be
-turned into the bath at a white heat In this way the metal will maintain its full
liquidity and heat, and consequently it will not readily solidify-when in the ladle
or elsewhere after being tapped from the furnace
In order to dilute or reduce the amount of the carbon contained in the metal soft
wrought iron must only be here used, that is to say, non containing less than 12
per cent of carbon, this latter being about the amount already in the metal, there-
fore iron containing 11 or 10 per cent of carbon or lower is used with advantage
for this object, and if a soft steel be required with carbon as low as 10 per cent it
is found best to use iron with nearly all the carbon worked out, or containing, say,
05 per cent, or lower, as then a less quantity can be charged than if the iron
contained more carbon The carbon contained in the whole may thus be reduced
to 06 or 07 before changing the fe110-inanganese, which added to the small amount
of carbon put in by the ferro-manganese will bring it to 10 per cent in the finished
Inetal. If the carbon contained in the metal before charging in the ferro-manganese
should have been reduced to 12 or 15 per cent by the first addition of wrought
1on, and the amount of carbon in the finished material be required to be not less
than 17 or 18 per cent then the amount or a little more of the feno-manganese
can be charged without putting in the second lot of wrought non The quantity of
ferio-manganese (say, 7 per cent), as stated below, will be found amply sufficient,
provided the quantity of manganese in the pig iron charged at first be made up
Some of the following kinds of wrought iron can be selected for the large chaige
of wrought iron Old on wire of various kinds, 11on1ail ends, bai or merchant iron,
scrap (which contains very little carbon owing to the frequent heatings which it has
undergone), plate and sheet cuttings, tin plate cuttings, charcoal sheet cuttings,
bundled up (which form of wrought on is suitable for a product containing 12 or
10 per cent of carbon), old angle non, T iron, and other like sections, all kinds of
old non forgings, or even small heavy wrought scrap on, such as nuts, bolts,
punchings, and the like, where more convenient forms cannot be obtained
For Nos 1, 2, and 3 qualities of soft steel this last change of wrought non must
be selected, according to freedom from sulphur and phosphorous, as well as for the
pei-centage of carbon it may contain
When the wrought non in this last operation bas disappeared from the banks, or
has become dissolved by the molten metal, a rabble or bar should be frequently
inserted and stirred about in order to assist in binging the same into close contact
with the other metal, thereby rendering it perfectly liquid and uniform with the
other existing metal This abbling should be renewed at intervals during half an
hour after the wrought non has disappeared from the banks, in order to bring the
metal into contact with the full heat of the furnace before tapping it into the ladle
A sample will now be found to contain from 6 or 7 to 11 per cent of carbon,
according to the quantity of wrought non charged at the last operation, and
according to the proportion of carbon contained in such wrought on A little

page_text: buint lime, say, 15 or 20 lbs, is now thrown in to assist in keeping a fluid slag, and
after 10 minutes 7 per cent (of the total amount charged exclusive of one) of
powdered fe10-manganese containing not less than 70 per cent of manganese is
now charged into the centre of the molten bath, which ferro-manganese will melt
in about 2 or 3 minutes, but in order to securo a perfect molting and union from 5
to 10 minutes should be allowed previous to tapping, and the metal should also be
well tabbled before running out.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said William Harvey, Einest William Harvey, and Alfied Harvey in the
Great Seal Patent Office on the 28th July 1877
WILLIAM HARVEY, ERNEST WILLIAM HARVEY, and ALFRED HARVEY, of Azoft
Villa, North Woolwich, in the County of Essex, Steel Manufacturers "IMPROVE
MENTS IN THE Manufacture OF SOFT STEEL OR INGOT IRON AND IN THE APPLI-
CATION OF THE SAME TO VARIOUS USEFUL PURPOSES"
Our said Invention relates to a process for the manufacture of so-called "soft
steel" or "ingot 11on" containing as low a per-centage of carbon as 10, or possibly
lower, oi, say containing an amount of caibon ranging from 20 to 10, that is to
say, a soft steel can be made by on Invention, at any notice, containing any desued
amount of carbon within the range mentioned above, the per-centages being
inclusive Such "soft steel," made in the manuer heroin-after described, is especially
suitable for wue ropes, telegraph wie (where very low electrical resistance is
requned), cable wie, and wie of various kinds which have to stand great clongation,
twist, breaking strains, or other tests, also for amour plates, engine and other
forgings, nail making, plates, sheets, hoops, and every purpose where metal is
requied of a quality superior to that of charcoal 11on, and where greater tensile
strength, ductility, and toughness are requied than can be obtained hom the best
wrought iron worked in the ordinary way
The furnace which we prefer to employ for this manufacture is the well known
so-called "Siemens regenerative" open hearth steel-melting furnace, which is heated
by coal, gas, and atmospheric ur, but any other regenerative gas or reverberatory
flat-bottomed furnace capable of supplying a heat sufficient to melt wrought non,
and keep the said wrought iron in a fluid or molten state for some time may be
used if desired
A tap hole is provided at the back of the furnace, through which the finished
metal is run out The said metal may be first run into a ladle of requisite capacity,
as in the usual manner, and is thence tapped into round, square, or other shaped
moulds, as may be requied to suit the purpose or purposes for which the metal is
intended
According to our improved process we charge on the bottom of the furnace (such
furnace having previously attained the highest temperature, or nearly so, which it
can command) from 40 to 50, or, say 45 per cent (of total charge, exclusive of ore)
of pig iron, the quality of which pig on will be herein-after specified To this
pig on we add on charging 10 per cent of ore, which ore will begin to oxidise the
carbon contained in the pig non so soon as the latter melts, and if the pig iron contain
less manganese than 15 per cent the manganese in the pig iron is made up by
changing, along with the pig iron, a sufficient quantity of spiegel eisen, for example,
if the pig iron contain about 15 per cent or more of manganese, then no spiegel eisen
1 chaiged, but if it contain, say less, or, say only 5 per cent of manganese then
spiegel eisen should be charged in sufficient quantity to make up the said amount
No 1 Quality The pig iron charged should consist of the following, viz -Swedish
charcoal pig iron, either alone or in admixture with No 1 Bessemer hematite pig
non, this should be used for purity of metal, that is, metal containing traces only
of sulphur and phosphorus, as for example, when a soft steel is required for wire

page_text: and like purposes where a low electrical resistance is an object, this resistance being
the same as in charcoal iron, while the strength of material produced will be much
greater
No 2 Quality Bessemer, hematite, or other equivalent pig iron alone is used
for this quality, as regards purity, but the metal made from this pig iron will be
equivalent in working properties, both hot and cold, and suitable for nearly all the
same purposes, it being inferior only as regards-the slight difference in the amount
of impunity The electrical resistance also of the wire made from this metal will
not much exceed that of No 1 quality This pig non should be used in the following
monotions
the same as in charco Iron, WHO THIS SUGngen of naal prouvou
greater
No 2 Quality Bessemer, hematite, or other equivalent pig iron alone is used
for this quality, as regards purity, but the metal made from this pig iron will be
equivalent in working properties, both hot and cold, and suitable for nearly all the
same purposes, it being inferior only as regards-the slight difference in the amount
of impunity The electrical resistance also of the wire made from this metal will
not much exceed that of No 1 quality This pig non should be used in the following
proportions
75 per cent (of total pig non) of No 1 Bessemer
25
23
"
No 3
"
No 3 Quality Bessemer hematite pig on to be used in the following pro-
poitions
25 per cent (of total pig iron) of No 1 Bessemer
75
33
33
No 3
"
This will be found useful in cases where the electrical test is immaterial, but wherein
a metal is required at a cheap rate, and suitable for all other purposes enumerated
above, it being only slightly inferior in working and other properties to Nos 1 and
2 qualities.
The one used should be Spanish or English he natite, which must contain but
little phosphonic acid The pig non is now melted under the full heat of the furnace,
as much oxygen as possible being worked, but so as to be only slightly oxidising,
the damper during this period being raised as high as possible consistent with
keeping the gas, so as not to "cut" the 100f 01 block The melting down of this is
effected in from 1/1, to 21/2 hours after charging
2
A
When the whole is melted a little more an is put on, in order to assist in decai bu-
11zing the metal, and the full heat is kept up until the ore has all worked off the
surface of the metal, or until the one has become reduced by the action of the carbon
contained in the pig non At this time the metal will be seen to sink below the
former level, and after some time it will boil uniformly over the entire surface
sample of the boiling metal should now be taken out, cooled in water, died, and
hammered on a smith's anvil, if on the fist blow it breaks and flies 1 cwt, about, of
ore should be thrown in, which operation is repeated until the sample stands a blow
on the anvil without facture, thereby indicating that the metal contains from 60
to 75 per cent of carbon When this point is reached from 30 to 40 per cent (of
total charge, exclusive of ore) 01, say 35 per cent of wrought iron or soft steel scrap
is changed on the banks of the furnace, in small quantities at a time, say 5 to 10 cwt
at either end, which wrought on, in whatever shape, is allowed to melt almost
entuely by heat while still on the banks, without being pushed into the bath of
metal That portion, however, of the wrought non o soft-steel scrap which is
charged much above the level of the metal may with advantage be turned in when
at a good white heat, in order to save waste by oxidation The object of this mode
of changing the wrought non or soft-steel scrap is to prevent the cooling of the
molten metal, which would probably result if the charges were intioduced without
previous heating, thereby incunning the risk of portions assuming a pasty condition,
instead of being uniformly thin and well melted Should the furnace, however, be
working very hot some of the wrought non or steel scrap may be turned in with
advantage when at a good heat During this melting in of the wrought on or
steel scrap the flame should be kept bordering on a non-oxidising quality
The object of changing the wrought-11on or soft steel scrap at this period is as
follows
1st By running it in, in the manner described, it liquifies and renders very
thin the thick scum or too silicious slag which accumulates on the surface of
the inolten pig 11on after being nenily decuburized by the ore, as is the case in
working the so called "pig and one" process, thereby preventing the heat (gas and
air) fiom penetrating through the metal, and so retarding the decai burizing effect

page_text: of the oxygen contained in the flame and increasing the liability of the said metal
to assume a pasty condition, and sinking to the bottom by reason of the deficiency
of heat, but after the wrought iron or soft steel scrap is run in, the slag being in a
very liquid state allows the heat and flame to penetrate perfectly, thereby pre-
venting the metal from sinking to the bottom
2nd Owing to the wrought iron containing but little carbon it is found that
when the whole of it is run in, in the manner described, the said wrought iron by
its diluting action and the oxygen in the flame by its decarburizing action (during
the tune the wrought on was melting) will have reduced the carbon contained in
the metal to not more than 14, or 15 and sometimes even lower, thus reducing the
carbon inuch quicker than by working with ore for the same object, as the time
required for the melting in of the wrought iron does not exceed one and a half hours,
though it is possible to work it in in less time than this
When the whole of this wrought iron or soft steel scrap has been melted and
tuined well in the bath of metal a rabble is inserted to ensure a thorough admixture
of the wrought iron or steel scrap with the other metal
A piece of ore should now
be thrown into the bath, and if after a minute or two the ore floats on the surface
and there appears to be no action between the metal and the oro, or the ore is only
reduced with difficulty, this is an indication that nearly the whole of the carbon
has been practically eliminated, that is to say, that the carbon contained in the
inetal has become so low that neither the ore nor the oxygen of the flame has any
perceptible "buining" or "taking out" action on the carbon that remains, but if
the ore disappears after 2 or 3 minutes this is an indication that a little more ore
is required, which is accordingly thrown in at intervals till there is no action, as
above explained When this is the case no more ore is required, but a full heat is
kept up for 15 or 20 minutes, so that the oxygen in the flame may possibly burn
out a little more of the carbon, and the metal will thereby be considerably heated.
The wrought iron for this stage may consist of the following
-
For No 1 Quality (herein-before referred to) Hammered slabs, blooms, or wie,
puddled or made from hematite, pig iron, or equivalent (to secure the purity), charcoal
11on sciap bundled up, or other bais, blooms, or scrap which contains very little or
only a trace of impurity, the carbon however is immaterial
For No 2 Quality Old bar iron, T iron, angle iron, and merchant iron scrap, or old
wie of any description, also soft steel scrap, ingot ends, plate cuttings, and the like
For No 3 Quality Old iron rails, bars, wrought scrap of any description, plate
cuttings, wrought-ion borings or turnings, and the like
If pig iron only be used, as is the custom at some works, or if instead of wrought
iron steel scrap be added to pig iron, and the whole decarburized either by the
oxygen in the flame or by the ore, the carbon by working in the said ore may be
reduced when the ore has no further action on the metal (as explained) nearly the
same figure as previously specified, namely, 14 or higher, which cannot further be
reduced by the oxygen of the flame or by the ore, hence more wrought iron of a
particular kind can by our Invention be now worked in the bath of metal with
advantage to reduce the carbon to a lower figure before charging with ferro-
manganese
When nearly the whole of the carbon has been eliminated the surface of the
bath of metal will show numerous thin and very liquid "pools" like water, ou
which pools the beat seems to have greater effect than on the remaining surface. A
sample now taken out will be found to contain about 12 per cent of carbon When
this point is reached wrought on ranging from 10 to 30 per cent or higher (of the
total charge exclusive of ore) is introduced according to the carbon required in the
finished metal, that is to say, if soft steel containing 10 per cent of carbon is
If 15 per
required, then from 23 to 30 per cent of wrought iron must be added
cent of carbon is required about 17 per cent of wrought iron must be charged, and
so on, the quantity charged being in proportion to the carbon required Such wrought
iron should be put in in quantities of about 5 or 6 cwts at a time, on each bank, and
allowed to melt in entnely by the heat of the furnace without pushing in any part

page_text: thereof, except that which is furthest away from the metal which should be turned
into the bath at a white heat In this way the metal will maintain its full liquidity
and heat, and consequently it will not readily solidify when in the ladle or else-
where after being tapped from the furnace
In order to dilute or reduce the amount of the carbon contained in the metal soft
wrought non must only be here used, that is to say, 11on containing less than 12 per
cent of carbon, this latter being about the amount alicady in the metal, therefore
11on containing 11 or 10 per cent of carbon or lower is used with advantage for this
object, and if a soft steel be required with 10 per cent or lower of carbon, itis found
best to use non with nearly all the carbon worked out, or containing say 05 per cent
or lower, as then a less quantity can be charged than if the iron contained more carbon
The carbon contained in the whole may thus be reduced to 06 or 07 before
charging the ferio-manganese, which added to the small amount of carbon put in
by the fetro-manganese will bring it to 10 per cent in the finished metal If the
carbon contained in the metal before charging in the feno-manganese should have
been reduced to 12 or 15 per cent by the fist addition of wrought on, and the
amount of carbon in the finished material be required to be not less than 17 or
18 per cent, then the amount or a little more of the ferro-manganese can bo
charged without putting in the second lot of wrought iron. The quantity of terro-
manganese, (say 7 per cent), as stated below will be found amply sufficient pro-
vided the quantity of manganese in the pig iron charged at first be made up
Some of the following kinds of wrought non can be selected for the last charge
of wrought iron Old non wie of various kinds, iron rail ends, bar or merchant
11 on sciap (which generally contains very little carbon owing to the frequent
heatings which it has undergone), plate and sheet cuttings, tin plate cuttings,
charcoal sheet cuttings, bundled up (which form of wrought 11on is suitable for a
product containing 12 or 10 per cent of carbon), old angle non, non, and other
like sections, all kinds of old on forgings, or even small heavy wrought sciap iron,
such as nuts, bolts, punchings, and the like, where inore convenient forms cannot be
obtained
For Nos 1, 2, and 3 qualities of soft steel, this last charge of wrought non must
be selected according to fieedom from sulphur and phosphorus as well as for the
per-centage of carbon it may contain
When the wrought non in this last operation has disappeared from the banks
or has become dissolved by the molten metal, a abble or bar should be fiequently
inserted and stirred about in order to assist in bringing the same into close contact
with the other metal, thereby rendering it perfectly liquid and uniform with the
other existing metal This abbling should be renewed at intervals after the
wrought non has disappeared from the banks in order to bring the metal into
contact with the full heat of the furnace before tapping it into the ladle, and to
ensure uniformity A sample taken will now be found to contain from 6 or 7 to
11 per cent of carbon, according to the quantity of wrought iron chaiged at the last
operation, and according to the proportion of carbon contained in such wrought
11 on From 20 to 30 lbs of lime is now thrown in to assist in keeping a fluid slag,
and after about 10 minutes, during which time the metal is rabbled, 7 per cent (of
the total amount chaiged exclusive of ore) of ferro-manganese (previously reduced
to sinall fragments and passed through a sieve of 5 holes to the inch), containing
not less than 70 per cent. of manganese 15 now changed into the centre of the
molten bath, which ferio-manganese will melt in about 2 or 3 minutes, but in order
to secure a perfect melting and union about 5 minutes should be allowed previous
to tapping, during which time the metal is again well rabbled Seven tons of this
soft steel or ingot iron can be made in from 71%, to 9 hours from the time of
charging.
Having now described and particularly ascertained the nature of our said Inven-
tion, and the manner in which the same is or may be used or canned into effect,
we would observe in conclusion that what we consider to be novel and onginal

page_text: and therefore claim as the Invention secured to us by the heroin-before in part
recited Letters Patent 19,-
First In the manufacture of what is known as ingot iron, the charging of pig
iron of the qualities herein specified in the proportion of fiom 40 to 50 per cent. of
the complete charge, exclusive of the ore, as herein-before described
Secondly The charging of the greater portion of the ore along with the pig iron
at the commencement of the operation in order to facilitate the decarburization, as
herein-before described
Thudly The charging, at the first stage of the operation, pig non containing the
required proportion of manganese, or the charging at the same stage the requisite
proportion of spiegel eisen to make up the required amount of manganese, as herein-
before described
Fourthly The melting in of wrought or malleable iron of the qualities herein
specified, so soon as the carbon in the bath of molten metal has reached a point of
from 60 to 75 per cent or thereabout, with a view to diluting the amount of carbon
in the bath, as herein-before described
-
Fifthly The melting in of a fun ther change of wrought iron in the proportions
and of the qualities hei ein specified so soon as the carbon in the bath has been prac-
tically burnt out for the purpose of futher reducing the proportion of carbon to
the desired point as herein-before described
Sixthly. The reducing the proportion of feno-manganese added before tapping
to as low a per centage as 7 of the whole change, exclusive of one, the said ferro-
manganese being by preference reduced to small fragments, as herein-before
described.
In witness whereof, I, the said Ernest William Harvey, for and on behalf of
myself and the said William Harvey and Alfred Harvey, have hereunto
set my hand and seal, this Twenty-eighth day of July, in the year of
our Lord, One thousand eight hundred and seventy-seven
ERNEST WILLIAM HARVEY. (L.S.)
0 Witness,
5
EDWIN PALEXANDER,
Consulting Engineer and Patent Agent,
14, Southampton Buildings,
Chancery Lane,
W C.