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No branch of industry has
risen more rapidly in Scotland than the manufacture of oils and other
products from native shales, nor has any been brought to such a high degree
of perfection within an equal time. Paraffin, which is so named on account
of its want of affinity with most chemical substances, was discovered by
Reichenbach in the year 1830, and about the same time by Dr Christison, of
Edinburgh, acting without any knowledge of Reichenbach's investigations.
After the discovery several patents were taken out for the making of oil
from schistus or shale. In 1833 Butler's Specification describes the process
for making oil from shale. Hompesch's Specification, dated 1841, describes
the process of making oil from schist, clay-slate, and asphalt. Du Buisson's,
dated 1845, describes the process of oil-making from the same material.
Selligue, previous to 1845, distilled oils from the shales of Autun, in
France.
In the year 1847 Professor
Lyon Playfair, while visiting a brother- in-law who owned a coal-pit at
Alfreton, Derbyshire, had his attention drawn to a thick, dark, oily fluid
which trickled from rents in the roof of the colliery, and was struck by the
idea that it might be transformed into some useful substance by proper
chemical treatment. He imparted his views to Mr James Young, then a
well-known chemist in Manchester, and suggested to that gentleman the
advisability of subjecting the crude liquor to chemical investigation, with
the view of testing the qualities it possessed. Mr Young took the hint, and,
in the course of the experiments which he made, found that the crude fluid,
on being distilled, yielded a pale yellow oil containing floating particles
of lustrous matter, which, on subsequent examination, proved to be crystals
of paraffin. Soon afterwards a factory for the distillation of burning and
lubricating oils from the crude petroleum of the coal-mine was established
at Alfreton by Mr Young. The enterprise was successful, and the new trade
was prosecuted with vigour and energy; but the factory had not been in
operation for two years when the supply of raw material ceased, and the
works, which were expected to develop a new branch of manufacture, were
brought to a stand. This untoward event had the effect of directing Mr
Young's energies to the solution of a problem to which he had given much
thought, and to the practical realisation of which he now looked for
continuing the supply of oil so unexpectedly cut short. Observation and
reflection had convinced him that the Alfreton petroleum was the product of
very simple natural causes, and these he set himself to investigate. Guided
by experience, he was led to the conclusion that the oil had its origin in
the distillation of coal by subterranean heat. In the course of two years,
during which he made many experiments, he was enabled to prove the
correctness of the opinion he had formed. He found that, by distilling coal
at a low temperature, he obtained a liquid of an oleaginous kind, similar in
its virtue and consistency to the natural oil. The primary difficulties of
the undertaking having been thus overcome, it became a question of pressing
importance to decide whether the discovery could be made available for the
purposes of trade. Unless it could be carried out so as to supply sufficient
material for the stills of the manufactories, it was apparent that the
discovery would be practically valueless. Subsequent experiments proved that
the crude oil could be extracted from any coal of a bituminous nature, and
that the largest quantity could be obtained from cannel coal. A suitable
mineral, therefore, was all that was now required to bring the scheme into
operation, and to obtain that the coal-fields were explored and their
qualities tested.
Some bituminous coal obtained
from Boghead, near Bathgate, in the county of Linlithgow, was tried by Mr
Young in 1850, and found to be peculiarly rich in oil. As the supply was
abundant, Mr Young, after taking out a patent for "treating bituminous coal
to obtain paraffin and oil containing paraffin," was joined by Messrs
Meldrum & Binney. They selected a site near the town of Bathgate, and
erected thereon an extensive establishment for extracting oil from coal, and
converting it into a variety of useful products. The works were put up under
the superintendence of Mr Meldrum, and were conducted under his active
management.
Such was the beginning of a
branch of trade which speedily assumed great importance, and converted the
quiet town of Bath gate, together with the adjacent villages, into a great
centre of industrial activity. The district was chiefly inhabited by
hand-loom weavers, whose miserable earnings—in many cases not exceeding 4s.
a-week—were barely sufficient to prevent starvation; and when the new field
of labour was opened up, the weavers gladly relinquished their looms, and
sought employment at the paraffin works. A proof of the marvellous success
that attended Mr Young's enterprise, and the deep hold that it took on the
district, is afforded by the fact that, though the population of the parish
and town of Bathgate had increased only from 2513 to 3341 between the years
1801 and 1851, the ten succeeding years witnessed an increase to 10,000. The
manufactory was extended until it covered a great space of ground; and the
value of its products was recognised throughout the world.
Mr Young's patent expired in
1864, but previous to that time several works were in operation for
distilling oil from shale. In the parish of West Calder a seam of shale
lying on the limestone on the estate of Mr Hare of Calderhall was worked by
Mr Gray, and the shale distilled at the Leavenseat Oil Works. About 1862 the
West Calder Works were erected on the estate of Gavieside, by Messrs Fell &
Co. About the same time Messrs Raeburn erected retorts at the Grange, on the
estate of Charlesfield. In the parish of Mid-Calder the Oakbank Works were
erected about 1863, on the estate of Mr Hare of Calderhall, by a limited
liability company. In the parish of Uphall there are several extensive
fields of shale. The Broxburn shales on the estate of the Earl of Buchan are
leased by Mr Bell, who is most energetic in developing the mineral resources
of that estate. About 1860 retorts were erected by Dr Steel of Wishaw at
Broxburn, to distil oil from shale supplied by Mr Bell. Early in 1862 the
Broxburn Shale Oil Company (Limited) was formed; but after expending a large
sum of money, it was wound up in about two years. The whole plant was sold,
and Mr Fertile, of the Saltney Oil Works, succeeded the company in the
occupation of the ground. After erecting upwards of 200 retorts, he sold his
work to a company called the Glasgow Shale Oil Company (Limited). This
company, as well as Mr Poynter at his works at Broxburn, are now producing
large quantities of oil from shale supplied by Mr Bell. In addition to these
works, Mr Bell has erected a large number of retorts; and Mr Hutchison has a
small refinery at Broxburn. It will thus be seen that Broxburn is one of the
most important seats of the oil trade. In the same parish of Uphall there
are extensive fields of shale on the estate of Mr A P Lagan, M.P. for the
county of Linlithgow; and that gentleman erected retorts previous to the
expiry of the coal oil patent in 1864. Shortly after the dissolution, in
1864, of the copartnery of Messrs E. Meldrum & Co. and of Messrs E. W.
Binney & Co., the firms under which Young's patent was worked, Mr Meldrum
became associated with Mr M'Lagan and Mr Simpson, of Benhar, in the Uphall
Mineral Oil Company, which purchased the works on Mr M‘Lagan's estate and
leased his shale. Through the experience and skill of Mr Meldrum in the
manufacture of paraffin oil, to which the prosperity of the Bathgate
Chemical Company was so much due, the oil manufactured at the Uphall Works
assumed at the first a position in the market second to none in the valuable
points of burning quality, purity, and safety. The Uphall Works have
recently been greatly extended, and are now the second largest in this
country.
Since 1864 several oil-works
have been erected, of which may be mentioned the Dundas Shale Oil Company,
on the estate of Mr Dundas of Dundas, at Kirkliston; the Westwood Shale Oil
Company, on the estate of Captain Steuart; the Hermand Company, belonging to
the Messrs Thornton, on the estate of Mr Maitland of Hermand—all of which
manufacture the crude oil only.
After the partnership under
which the Bathgate Chemical Works had been established was dissolved, Mr
Young carried on the concern by himself for a year, during which time he
conceived the idea of creating new works in the neighbourhood of
West-Calder—a district particularly rich in bituminous shale. Having
acquired necessary leases, &c., Mr Young chose a site on the estate of
Addiewell, about a mile west from the village of West-Calder, and began the
construction of an establishment on a more extensive scale than that at
Bathgate. There was no accommodation in West-Calder for a large body of
workpeople, and Mr Young's first care was to provide lodging for his workmen
by building a range of houses. A bed of clay was discovered on the property,
a brickwork was erected, and soon houses to the number of several hundreds
were provided, the building of the manufactory being at the same time pushed
forward. After considerable progress had been made, Mr Young organised a
company to undertake the working of both the Bathgate and Addiewell
establishments. The new copartnery, under the designation of Young's
Paraffin Light and Mineral Oil Company (Limited), has been in existence for
about three years, Mr Young, besides holding stock to a large amount,
occupying the place of general manager. A brief description of the two
manufactories of the company will convey some idea of their extent and
importance.
The Bathgate Chemical Works
are situated about a mile from the town. They occupy twenty-five acres of
ground, and are connected with the main lines of railway in the vicinity by
branch lines, which afford convenient conveyance for the raw material to any
desired point, and for sending out the manufactured goods. The various
departments are admirably arranged, and the appliances in all are so
completely adapted to their purpose that it is difficult, after examining
them, to believe that the manufacture of paraffin is really only a thing of
yesterday. From a distance, the establishment has the appearance of a
village of irregularly built grimy houses. A nearer view reveals a series of
broad thoroughfares lined with retorts, stills, boilers, tanks, &c., some
under iron roofs, and others exposed to the weather.
In order that he may
understand what is going on around him, the visitor must begin at the
coal-breaking shed. The coal used is a hard, rusty-black-coloured mineral.
It is brought in from the pits in lumps of considerable size, and the first
step in the process of manufacture is the breaking of these into small
pieces, which may be conveniently shovelled into the retorts. There is a
powerful crushing-machine for performing this part of the work. Contiguous
to the breaking shed, the retorts, which are 200 in number, are ranged in
sets of four each. The retorts are simply vertical cast-iron pipes twelve
feet in length and fourteen inches in diameter. Each set of four retorts is
built into a furnace, the lower part of the pipes being embedded in
brickwork, while several feet of the upper end are left free. The retorts
have funnel-shaped tops, and are fitted with air-tight stoppers. The lower
extremity projects downwards through the furnace into a pit filled with
water, an arrangement which, while it effectively shuts out the air, admits
of the exhausted cinder being withdrawn without interruption. As the work
goes on, the waste is withdrawn gradually, and fresh coal is added. The
portion of the pipe which passes through the furnace is maintained at a dull
red heat, and that is the point at which the distillation actually takes
place. Under the influence of the fire, the coal is decomposed, the oil
being driven off in the form of vapour, which is collected in a large main
pipe having a connection with all the retorts. This main pipe conveys the
oil vapour to the condensers, which are similar to those used in gas-works.
The condensers stand outside, and, as the vapour passes through them, it is
reduced to a liquid form. It is always found that a portion of the vapour is
in- condensable, and that portion is collected in a gas-holder, and is used
for lighting the workshops. The liquid formed in the condensers is run off
into a reservoir capable of containing 100,000 gallons. At this stage the
oil has a black greasy appearance, like natural rock oil or petroleum, and
gives off inflammable vapours at the usual atmospheric temperature. The tank
is fitted with an airtight covering of iron for the purpose of restraining
this vapour, and lessening the chances of its ignition. Another precaution
against loss by fire consists of a large pipe inserted into the roof of the
tank, and so arranged that, in the event of the oil taking fire, a strong
jet of steam could be at once sent in, and the flames be thus extinguished.
The crude oil obtained by
distilling the coal as described is subjected to various other processes,
under which it yields four different products—namely, paraffin oil for
burning, paraffin oil for lubricating machinery, a light volatile fluid
called naphtha, and solid paraffin; but before any separation of these takes
place, the oil has to be thoroughly purified. It is first distilled, which
is performed in a range of huge cylindrical stills, laid in a horizontal
position. When the vapour from the stills is condensed, it is collected in
tanks, and presents a wonderful improvement in appearance. The black
sluggish stuff from the stock-tank has been converted into a dark-green
limpid fluid. The impurities extracted from the crude oil are removed from
the still after each charge. They form a large black lustrous substance,
resembling coke, and make excellent fuel. Though much improved by the
distillation, the oil is not yet sufficiently pure, and requires further
treatment. It is run into circular iron tanks; and, after a certain quantity
of sulphuric acid is added, the liquid is violently agitated by a revolving
stirrer. The acid has no affinity for the finer oil, but it has for the
foreign substances which the oil holds in solution. At the end of four
hours' agitation, the oil is seen to have become of a pale green colour; and
on the liquid being allowed to settle, the vitriol and the organic
impurities, by reason of their greater weight, collect in the bottom of the
tank, and, when drawn off, this sediment is used for fuel. The oil is next
transferred to a clean set of tanks, in which it is mixed with a strong
solution of caustic soda, and again subjected to agitation. The soda
neutralises any sulphuric acid that may remain in the oil, and rids it of
impurities which were not affected by the vitriol. The oil is then distilled
a second time, and the treatment with sulphuric acid and soda is repeated.
After these operations, the oil presents a clear, pale, yellow colour, and
in that condition it contains the elements of the four products mentioned
above. To separate these, and make them available, is the next care of the
oil-makers. This is accomplished by distilling the oil at various
temperatures.
The first product taken off
is naphtha, for the separation of which only a gentle heat is required.
Naphtha is a valuable liquid, extensively employed in the arts, and as an
illuminator. By raising the temperature of the stills after the naphtha
vapour has passed off, paraffin oil is obtained. Before being ready for the
market, both the naphtha and the oil are distilled separately, in order to
make them perfectly pure. The oil is the most valuable and important of all
the articles manufactured at Bathgate, and is extensively known for its
illuminating qualities. In country districts, where gas is not manufactured,
the paraffin oil has almost entirely superseded the other kinds of oil, and
is universally admired for the clearness and brilliancy of the light which
it affords. One gallon of the paraffin oil is equal in illuminating power to
one and a quarter of American petroleum oil; and it can be produced at a
price which gives a light cheaper than English coal gas. Another, and not
the least important virtue which paraffin oil possesses, is the safety with
which it can be used for domestic purposes. Great care is taken to separate
the least trace of naphtha from it, so that there is no risk of explosion by
accidental ignition.
When all the finer oil has
been distilled over, the heat is increased, and a heavier vapour is driven
off. This last produces a thick oil, which, when thoroughly cooled, assumes
the consistency of grease. It is in reality a mixture of oil and solid
paraffin. When the paraffin has been crystallised by cooling the liquid, it
is separated from the oil by a process of filtration under pressure. The
department in which the separation is accomplished is fitted up with
hydraulic presses. The heavy oleaginous liquid is put into strong canvas
bags, and these are placed in the hydraulic presses, and squeezed until all
the oil is forced through the texture of the bags. The oil extracted in this
way is an excellent fluid for lubricating machinery, and is largely used in
cotton mills and other establishments in which machinery of a delicate kind
is employed. Two valuable peculiarities of this oil are that it does not
become rancid, and that it is free from all tendency to spontaneous
combustion.
The solid paraffin is now the
only substance left. After the oil is extracted, the paraffin is emptied out
of the bags. It is then of a dirty-yellow colour, and requires a deal of
purification before it assumes that beautiful wax-like appearance by which
it is distinguished The stuff is placed in iron vessels containing heated
naphtha, by which it is dissolved. The naphtha acts on the impurities, and
after a certain time the liquid is allowed to cool, when it again assumes a
degree of consistency. It is then subjected to filtration in canvas bags as
before. This operation of dissolving the paraffin in naphtha, cooling it,
and filtering it through bags, is repeated until the substance has acquired
the requisite whiteness and purity. On being taken from the filters for the
last time, the paraffin is removed to a workshop in which it is subjected to
the action of steam, which carries off the odour of the naphtha; and the
paraffin, in a liquid state, is run into circular iron moulds, in which it
solidifies. As thus finally purified and crystallised, the paraffin is a
fine white substance, more transparent than wax, and of a beautiful lustrous
structure. It lacks both taste and smell, burns with a white flame, without
smoke. Candles made of it are in much favour, both on account of the
brilliant light they afford and the clearness with which they burn.
The Addiewell Chemical Works
occupy seventy acres of ground, fully one-third of which is covered by
buildings, tanks, condensers, &c., while a large portion of the remainder is
taken up by railways and roads which give access to all parts of the vast
establishment. It is difficult to believe that the many buildings and
peculiar-looking iron structures which stud the ground are parts of one
concern, and that they are not a gathering of a dozen factories used for
widely different purposes. The system of iron pipes which passes overhead,
beneath the feet, and crops up in all quarters, would be sufficient, one
would think, to carry the gas and water supply of a large town. The retort
sheds, taken together, are upwards of 200 yards in length, and each contains
a double row of retorts. The main pipe which collects the vapour from the
retorts and conducts it to the condensers is nearly a yard in diameter. The
condensers are on a like gigantic scale, each containing several miles of
piping. As the processes at Addiewell are similar to those at Bathgate, it
is unnecessary to explain them further. In addition to the four articles
specified as being the chief products of the shale, a fifth substance of
recent discovery has to be mentioned. It was discovered that the water which
accompanies the oil through certain stages of the manufacture contained
traces of ammonia, and by experiment it was found that the ammonia might be
profitably extracted. There is now a special department for separating the
ammonia, which is done by treating the water with sulphuric acid, and so
producing sulphate of ammonia. This substance fetches L.16, 10s. a-ton, so
that its preservation was well worthy of attention.
An interesting department of
the Addiewell Works is that in which candles are made. Most persons are
familiar with the beautiful candles made from Young's paraffin. They are to
be found in every market of the world, and are manufactured in various parts
of England and abroad, the paraffin being supplied from the works of the
company in the large round cakes mentioned above. Before the discovery of
these candles, Baron Liebig wrote It would certainly be esteemed one of the
greatest discoveries of the age, if any one could succeed in condensing coal
gas into a white, dry, solid, odourless substance, portable and capable of
being placed in a candlestick." The jury of the Great Exhibition of 1851
say:- "This very problem Mr Young appears to have accomplished, by
distilling coal at a low temperature;" and they express an opinion that "
the brilliant discoveries of Chevreul, but lately threatened by the
splendour of the electric light, may be eclipsed by the general adoption of
solidified coal-gas candles." Professor Hoffman, reporting for the jury of
the Great Exhibition of 1862, describes "Mr Young as the founder of this
industry," and speaks of the specimens exhibited "as realising the great
problem which the rare sagacity of Liebig pointed out ten years ago." The
candles are made by ingeniously devised machines, in which the paraffin,
after being poured into the moulds is rapidly solidified by currents of cold
water. Many hundredweights of candles are turned out weekly, though the
department is the smallest in the establishment.
In the manufacture of
paraffin, a great quantity of illuminating gas of a superior quality is
produced. The town of Bathgate obtains its supply from the Paraffin Works,
and the people of West- Calder have been considering the advisability of
lighting their now rapidly increasing village with gas from Addiewell. It is
a somewhat astounding fact that one and a quarter million cubic feet of gas
are made every day at the Addiewell Works, for which, after subtracting what
is necessary for lighting the establishment, no other use can be found than
the heating of boilers and the like. It is stated that an offer was made by
the company to supply the city of Edinburgh with gas at the rate of ls. 6d.
per thousand cubic feet.
The company's works at
Bathgate are being supplied with raw material from the pits adjoining
Addiewell, so that there is a constant traffic between the two places. Five
locomotives are kept fully employed in the carrying department. Some of the
pits lie close to the manufactory, and none of them are beyond a distance of
two miles. The company have four hundred miners, and in the other
departments upwards of a thousand persons are employed. A great part of the
work is done by unskilled labourers, who receive from 16s. to 19s. a-week.
There is a large staff of mechanics who execute most of the ironwork
required; and in addition to these there are joiners, masons, plumbers, and
others who find constant occupation in the great but still growing place.
The houses provided for the workpeople are commodious and comfortable, and
they are let at very moderate rents. A school, under Government inspection,
is also attached to the works.
Taken collectively, upwards
of 3000 persons are employed in the Scotch mineral oil-works, and an immense
sum of money has been invested in the several concerns. The trade recently
experienced a period of depression, arising from the extensive importation
of low- priced oils from America; but now that the public have had an
opportunity of comparing the native with the foreign article, confidence in
the former is being restored, and at no time during the past three or four
years has the trade been in a more healthy state than now. Several of the
oil-works which had been stopped for a time are in operation; and on all
sides extensions are in progress. Mr Young's little factory at Alfreton was
the parent not only of the Scotch mineral oil trade, but also of that of
America; for until he began operations, oil had never been distilled to
produce an article of commerce. The oil trade of Scotland is worth many
hundreds of thousands of pounds annually, and that of America is estimated
at ten millions. It has been rarely that an inventor has lived to see such a
splendid outcome of his ideas, or to be a partaker, as Mr Young has been, of
the wealth created by his discoveries. To any one who takes an intelligent
interest in the manufacturing industries of the world, there could be few
things more enjoyable than to walk over the great chemical manufactory at
Addiewell in company with Mr Young, and hear him quietly relate, in answer
to your queries, how he devoted himself to reveal some of the mysteries of
nature, and convert to the use of mankind what were apparently the meanest
among the contents of her storehouse. The story of Mr Young's life and
labours is as interesting as almost anything to be found in the whole range
of industrial biography. |
