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Modern chemistry has become
an essential of many industries. It has not only revealed the marvellous
substances and forces inherent in solids, liquids, and gases, but has shown
how they can be practically utilised in connection with a large number of
industries besides that specifically termed chemical. In this wider sense it
should be regarded as a primary industry. But as a specific industry it is
not so extensively carried on in Scotland as any of the foregoing and may,
therefore, comparatively be treated as a secondary one.
In the narrower sense, it was
introduced at Glasgow towards the end of the eighteenth century by Mr
Charles Macintosh, who began the manufacture of sugar of lead and chloride
of lime, and also of waterproof cloths. In the first year of the nineteenth
Messrs Tennant, Knox & Co. originated the factory at St Rollox for the
manufacture of sulphuric acid, chloride of lime, soda, soap, etc., which
prospered into one of the most extensive chemical works in the world, whose
monster chimney, 435^ feet high, is one of the prominent landmarks of the
city. These works now form part of the great combination known as the United
Alkali Company of Britain, and the more recent works of the Eglinton
Chemical Company and the Irvine Chemical Company are also included in this
combination. Its chief products are sulphuric acid, hydrochloric acid, salt
cake, bleaching powder. Formerly the alkali works produced large quantities
of soda ash (carbonate of soda) and caustic soda by the Leblanc process. In
1876, for instance, about 50,000 tons of common salt were converted in
Scotland into these substances. This process was gradually displaced by the
Ammonia Soda process, which, however, is now confined to England, and the
Scottish works at Glasgow, Irvine, Kirkintilloch, and other places are
devoted to
the manufacture of acids of
various kinds, as well as sulphitae. Epsom and other salts, sulphates,
borax, phosphates, etc.
Ammonia is obtained mainly as
a bye-product of other industries, such as gasworks, paraffin oil works,
works for the recovery of blast furnace gases, and in recent years the
manufacture of sulphate of ammonia has been extensively developed from these
sources. "Among the first to take up the subject of the recovery of tar and
ammonia from blast furnaces," says Mr Jones in a paper dealing with the
origin of the industry in the Journal of the Iron and Steel Institute for
1885, "was Mr William Ferrie, of the Monkland Ironworks. . . . This
important problem was (also) taken up in 1879 by Mr John Alexander and Mr A.
K. M'Cosh, of the firm of William Baird & Co., and the condensation ideas or
principles have been handled by them in a most masterly fashion. The first
large scrubber was erected by them at Gartsherrie in 1881, and the second in
1883. Almost simultaneously the subject was attacked by other ironmasters,
notably by the Messrs Neilson of the Summerlee Ironworks, and the Messrs
Addie of Langloan. . . . Mention should also be made of the names of Mr
Henry Aitken, Mr J. Chapman, and Mr Gorman. ... At the Gartsherrie
Ironworks, Coatbridge, and the Lugar Ironworks and Muirkirk Ironworks,
Ayrshire, the Messrs Baird have erected gigantic plant for carrying out the
above principle (the Alexander and M'Cosh process). They have in fact been
the pioneers of this industry, and the extraordinary amount of courage and
ability which they have shown in finally bringing things to a complete
practical success is worthy of the highest admiration."
Fifteen years later the
industry had made substantial progress. "In 1885," says Mr Henry Bumby
writing in the same journal for 1901, " the recovery of tar and ammonia from
the blast furnace was an infant industry just emerging from the region of
small scale experiment. At the present time, with one exception, every works
in Scotland either has a complete byproduct plant or is erecting one, and
all the earlier plants have been considerably enlarged and improved. ... In
designing these improvements no one has done more than Mr A. Gillespie, of
Glasgow, and the three by-product works recently erected to his designs are
admittedly the 'show' plants of the country. . . . The amount of sulphate of
ammonia recovered at the different works varies from 20 to 25 lbs per ton of
coal used in the furnaces, and the pitch and oil from 150 to 200 lbs.—the
variations depending largely on the nature of the coal used."
The progress of the industry
may be measured from the fact that during the decade 1889-99 the number of
tons annually produced rose from about 40,000 tons in the former year to
nearly 73,000 in the latter. In the same period the number of works in which
sulphate of ammonia was made increased from 51 to 63. Its value as a manure
accounts in part for the growing demand represented by these figures.
The manufacture of
dichromates of potassium and sodium, so largely used in the preparation of
pigments, such as chrome yellow, has also been carried on in Glasgow for
nearly a century. The cyanide process of gold extraction adopted in 1888-89
gave a great impulse to the production of potassium cyanide, which was
previously used mainly in photography and electro-plating. The Cassel Gold
Extracting Company, the owners of the patents for the new process, built a
factory in Glasgow to meet the increasing demand for this salt, and large
quantities were made and exported to the Transvaal and other gold producing
countries. The Company acquired the exclusive right to use the process
devised in 1890 by Mr Beilby, who became one of its directors and its
scientific expert, and built an additional factory at Glasgow. The
manufacture of ferro-cyanide, which is recovered from crude coal gas,
displaced that of alum in the works of the Hurlet and Campsie Alum Company
at Lennoxtown, Falkirk, and Hurlet, the supply of alum shale, which had long
been the staple manufacture at Campsie, having become exhausted about 1880.
The distillation of wood
yields acetic acid, methyl alcohol, acetone, wood tar, and other chemical
products, and these products are manufactured at Camlachie Chemical Works,
the Cart-vale Chemical Works, Paisley, and elsewhere. Coal tar and blast
furnace tar are distilled into naphtha, light oil, creosote oil, heavy oil,
and by the end of the nineteenth century the number of tar distilling works
in Scotland had increased to 46. From naphtha and light oil, benzine, which
is largely used in the manufacture of aniline, and from creosote, carbolic
acid, antiseptics, and sheep dips are produced.
The discovery of nitro-glycerine
by Sobrero in 1846 was utilised some years later by Alfred Nobel as a liquid
explosive in mining. Its defects and dangers as an explosive led to the
prohibition of its manufacture in Great Britain, but after further
experiments Nobel succeeded in overcoming these drawbacks by the invention
of dynamite, the manufacture of which was taken up by Nobel's Explosives
Company at Ardeer in Ayrshire. During the last quarter of the nineteenth
century the Company grew into a vast concern. In 1876 its operations were
confined to the production of dynamite, nitric acid, and detonators; since
then it has added the manufacture of blasting gelatine and its
modifications, gelatine dynamite and gelignite, ballistite or smokeless
powder and its modification, cordite, picric acid for lyddite, guncotton for
cordite, compressed guncotton for torpedo charges, shells, military and
naval guns, armour piercing projectiles, etc. Besides Ardeer it possesses
three other factories in Scotland—two near Polmont and one at Linlithgow,
and the growth of its operations may be gauged from the fact that its
scientific staff increased from 5 in 1876 to 53 in 1900, and the number of
its workmen from 102 to over 4000.
Compressed and liquified
gases are manufactured by the Scottish and Irish Oxygen Company established
at Polmadie in 1888. Compressed oxygen is used for the lime light, for
brazing and. lead burning, for respiration in case of asphyxia, and in
diseases of the lungs and heart. Another product, compressed carbon dioxide,
is applied in refrigeration and in the preparation of aerated waters. The
production of iodine from kelp, imported from the Hebrides, Ireland, and
Norway, showed a marked decrease during the second half of the nineteenth
century. In 1846 there were 20 factories in the West of Scotland; in 1900
the number had fallen to 4, which were situated at Falkirk, Clydebank,
Kilwinning, and Bonnybridge. The fall in the value of potash salts, in
consequence of the working of the deposits at Stanfurt in Germany, and the
growing importation of Peruvian iodine were chiefly responsible for this
decline.
In Edinburgh several firms
devote themselves to the manufacture of fine chemicals. Naturally in the
city, which has long been the seat of one of the greatest medical schools of
the world, medical chemicals occupy a foremost place. Among these
chloroform, which Sir James Simpson was the first practically to apply, is
largely produced. Other important products are morphine, caffeine, cocaine,
theobromine, strychnine, salicin, capsicin, podophyllin. Surgical dressings,
chemical manures (super-phosphates), and fertilisers (fish manures) are also
manufactured in considerable quantities. The manufacture of vulcanite and
other rubber goods is extensively carried on, whilst gelatine and glue are
manufactured at Gorgie and Cramond. Medical chemicals in great variety and
fertilisers (including basic slag) are also produced at Glasgow, whilst
Paisley takes the lead in the production of starches.
In the last quarter of the
nineteenth century a marked development took place in the manufacture of
paints and colours and the preparation of varnishes. Coal tar dyes came to
be largely used in the making of colours; liquid paints, enamels, prepared
distemper colours and stains were introduced, and the quality of paints
improved with the improvement of grinding machinery. Colours which were
formerly rare became more widely available in consequence of the new
processes which lowered their price. A similar development is observable
during the same period in the soap and glycerine manufacture. Whilst
formerly tallow was almost the only fat used in soap making, the use of
vegetable and nut oils resulted in the production of a superior quality of
soap (quick lathering or self-washing soaps). Another important advance has
been the recovery, by means of a simple process, of glycerine as a
bye-product of soap works, which is now manufactured in the two forms of
crude glycerine, and chemically pure glycerine—the last being mainly used
for medical and pharmaceutical purposes.
The dyeing industry received
a great impulse from the production from coal tar by Mr W. N. Perkin of a
violet colouring matter to which the name of mauve was given. Mr Perkin
carried out his experiments in the dyeworks of Messrs Pullar at Perth. A
great demand sprang up for this dye until it was superseded by a new violet
of a brighter colour. Many other aniline colours followed, all produced from
coal tar, and the Perth works of Messrs Pullar and Messrs Campbell were
successively enlarged to cope with the demand of this rapidly increasing
industry. Perth, with its railway facilities and its abundant water supply
from the Tay, was admirably fitted to become the arena of the enterprise of
the Pullars and the Campbells, which furnished employment to several
thousands of workers. The Perth dyeworks are mainly devoted to job-dyeing
which embraces every kind of garment, household requisites from lamp shades
to carpets, boots, gloves, etc. Dyeing is a process which requires
considerable chemical knowledge and great care in the use of the various
acids and alkalis on the part of the worker. Fibres belonging to the
vegetable kingdom (cotton, flax, hemp, jute, etc.) have to be treated
differently from fibres belonging to the animal kingdom (wool, silks, etc.)
On the former acids act injuriously, while alkalis have the same effect on
the latter.
"A dye house," says a writer
in the Bankers Magazine, in describing the process as carried out in these
works, " is divided into sections, each controlled by a foreman, and in each
of these sections a separate colour is, generally speaking, dyed. It is
quite remarkable how perfectly the dyer strikes the exact shade for each of
the innumerable patterns put into his hands. ... It is first of all immersed
with other goods for the same colour, and which have been similarly
prepared, in a great vat, in which the' necessary dyestuff has been
dissolved, and the goods are kept constantly on the move for at least an
hour and a half. They are then taken out, washed up, if necessary, and the
water extracted from them in a hydro-extractor, from where they are conveyed
to the stoves for drying thoroughly. From thence they pass through the hands
of the examiners, who, if they find all correct, pass them to the finishers,
who iron, press, or calendar the goods, according to what they are, and they
are then sent to the warehouse for dispatch to the customer."
The technical training in
bleaching and dyeing m Scotland was greatly benefitted by the grant of
£10,000 made in 1907 by the Trustees of Mr T. Graham Young, to assist in
making provision for the teaching of this subject in connection with the
Chair of Technical Chemistry in the Glasgow and West of Scotland Technical
College.
The manufacture of dyes
received a great impulse from the interruption of the import from Germany
caused by the war. Before 1914 the Germans had acquired a well-deserved
supremacy in the production of aniline dyes, and even the strong prejudice
against everything German which the war evoked could not contest this
supremacy. The German has been quick to apply scientific results and methods
to industry, and this is specially apparent in the chemical industry in
general and the dye industry in particular. The British Chemical Mission to
Germany after the war has frankly recognised the fact, and nothing but harm
can result from the fanatic tendency inspired in prejudiced minds by
national passion, masquerading in the guise of patriotism, to ignore or
belittle it. "Whilst," to quote the summary of the report of the Mission,
"preeminent as manufacturers of the so-called heavy chemicals—sulphuric
acid, soda, soap, etc.—we hold but a minor position as regards the
manufacture of fine chemicals, intermediates and dye stuffs; in particular
we have failed to hold and extend the dyestuff industry, although this
industry was originated here." At the same time the war quickened the
scientific resource as well as the energy of the nation, and one result of
the war pressure was a marked advance in the home manufacture of dyestuffs.
"Before the war," said the Chairman of the Bradford Dyers' Association at
the annual meeting of the Association on the 27th February, 1920, " not 10
per cent, of the aniline dyes used in the United Kingdom were made in this
country, and the total weight manufactured would not exceed 2,000 tons a
year. We have it on the authority of the Board of Trade Journal of the 5th
instant, that the production is now 25,000 tons a year, which is more than
20 per cent, in excess of the total weight of aniline dyes consumed in this
country in the years immediately before the war, and I think it may be
safely said that the progress made by the colour-making industry since 1914
has been greater than those having real knowledge of the difficulties and
the problems involved would have thought possible ... It is true we have not
the variety, and that we lack some of the best colours, but, on the other
hand, it is beyond question or doubt that in the supply of dyes we in this
country are in a much better position than any other country in the world,
not excluding Germany." It should be noted, however, that this optimistic
conclusion is not altogether shared by the Chemical and Dyestuff Traders'
Association, which in a recent memorandum to the Board of Trade (October,
1920) pointed out that the policy of making the United Kingdom independent
of external supplies of chemicals and dyestuffs had not been successful in
securing either the range, quality, or quantity of the materials supplied by
State-aided home enterprise.
Sugar refining made great
progress during the first three-quarters of the nineteenth century. Greenock
became the centre of the industry, which was also started in Glasgow,
Port-Glasgow, Leith, and Dundee. In 1812 there were 5 refineries at
Greenock; in 1860 the number had increased to 16. There were three at
Glasgow, two at Leith, and one at Port-Glasgow. The growth of the industry,
from about the middle of the century, is apparent from the rapid rise of the
tonnage of raw sugar refined in the Clyde works. In 1857 the number of tons
imported was 38,836; in 1862 it passed the 100,000, and in 1867 it stood at
178,013. During the last quarter of the century it showed a marked tendency
to decrease. In 1875 the number of refineries in operation at Greenock h^d
fallen to 13, whilst those at Glasgow and Port-Glasgow ceased operations. In
1900 the number had fallen to 5. The decrease was not due to lack of
enterprise on the part of the manufacturers, but in the main to the bounties
granted to foreign refiners who were thereby enabled to sell at a cheaper
rate in the British market. The consequence was that whilst the consumption
of refined sugar in Great Britain increased from 860,000 tons in 1875, of
which all but 100,000 was produced in this country, to 1,489,000 in 1900,
nearly one million of this latter quantity was imported from abroad, chiefly
from the Continent, and the quantity refined in Britain had dropped by
150,000 tons. The refining process, generally described, consists in the
dissolution of the raw sugar in water, the filtration of the liquid first
through cotton cloth and then through charcoal, and its concentration into
sugar crystals. Various appliances have been invented in the course of the
century whereby the various stages of the process have been improved.
Great progress has been made
in the production of sweets and the preserving of fruits, meat, and
vegetables. Confectionery is largely made in Edinburgh, Glasgow, and Dundee.
Dundee long took the lead in the manufacture of jams, of which Mr James
Keiller was the pioneer in the first half of the nineteenth century. The
proximity to the orchards of the Carse of Gowrie explains this early
predominance in jam making, to which Mr Keiller ere long added the making of
marmalade. The demand for this preserve spread from Dundee to other parts of
Scotland and ere long to England and ultimately to foreign lands. The
success of the enterprise led to the extension of the industry, not only in
Dundee and the adjacent region (Coupar-Angus, New-tyle, and Blairgowrie),
but to other centres in Scotland. Fruit preserving led too to a great
development of fruit growing in districts suitable for fruit culture,
notably in Clydesdale, the Strathearn and Blairgowrie districts of
Perthshire, and parts of Stirlingshire. Crieff, Carluke, Glasgow, Edinburgh,
as well as Dundee, acquired prominence in the preserving industry, which
includes the production of jams and jellies made from a variety of imported
as well as home grown fruits.
The centre of the meat
preserving industry in Scotland is Aberdeen, where it was introduced by Mr
John Moir in 1822 and whence it was extended to Peterhead, Glasgow, and
Leith. Nine establishments for preserving provisions were in operation in
Scotland about fifty years later, five of which belonged to Aberdeen. In
addition to these five there were three engaged in salting meat, and the
total output of preserved meat, fish, game, vegetables, etc., from these
Aberdeen factories was valued at £221,000 per annum.
Papermaking, already of
considerable extent towards the end of the eighteenth century, made rapid
progress in the first half of the nineteenth. This progress was accelerated
by the repeal of the duty on paper in 1861. The twelve mills in the
Edinburgh district in 1773 had increased to twenty-two in 1868 and the total
for Scotland in the latter year was fifty-seven. The villages on the Esk and
the Water of Leith are still the centre of the industry, which is also
carried on at Airdrie, Caldercruix, Paisley, Milngavie, on Tayside at Guard
Bridge and Dundee, at Aberdeen, and elsewhere. Rags were long the raw
material of the manufacture, and it was not till past the middle of the
nineteenth century that esparto grass and wood pulp were utilised. Machinery
for reducing the raw material to pulp was invented in Holland about the
middle of the eighteenth century and ere long superseded the more primitive
method of pounding the fermented rags in large mortars. Many years elapsed,
however, before Mr Robert produced a machine for converting the pulp into
paper in place of the old tedious manual process. This machine was improved
by the Messrs Bertram of Edinburgh, and the machine exhibited by Mr George
Bertram in the exhibition of 1862 was adjudged to be incomparably the best
hitherto constructed. Further improvements in the machinery for preparing
the pulp and producing the finished article have been made, and at Edinburgh
several engineering firms are now employed in the production of this
machinery.
Edinburgh and district have
also long had extensive milling, baking, and brewing industries. There are
large flour mills at Haymarket, Stockbridge, and Leith, and the biscuit
factories are also a special feature of the city's industrial products. The
fact that Midlothian has long been a rich agricultural county and takes
first place among the Scottish comities in the production of wheat and
barley, though only fifth in that of oats, explains the rise of the milling
industry. Its development has, however, depended on the large importation of
grain into Leith, which alone suffices to meet the demand of the millers.
The extensive brewing industry is due to the supply of water of a specially
appropriate quality derived from the strata of the Upper Old Red Sandstone
on the southern side of the city and at Duddingston, where quite a cluster
of breweries has sprung up in recent years. Brewing is also extensively
carried on in the Wellpark Brewery at Glasgow, whose establishment dates
from the middle of the eighteenth century, and a speciality of the
production in the west is Tennent's Lager and Munich Beers. Breweries are
numerous throughout the country, but the tendency during the last twenty
years has been to diminish the number of the smaller ones. The small brewery
can no longer compete with the large one. In Scotland the number in 1899 was
129; in 1912 it had fallen to 79. In the same period the production fell
from 240 million barrels per annum to about 200 millions. The export from
Scotland was 136,000 barrels in 1912, or 7 per cent, of the total
production.
There has been a marked
advance in the distilling of whisky since the middle of the eighteenth
century, when about 50,000 bolls of barley produced 504,000 gallons, which
at a duty of 7d. per gallon yielded £14,700 revenue. In 1911 the production
in the United Kingdom had reached 27,093,197 gallons, which at 14s. 9d. per
gallon yielded close on 20 millions of revenue. In 1786 the first distillery
was established at Glasgow—the fourth licensed in Scotland. The increased
taxation on malt gave rise to smuggling and the illicit still was in
operation all over the Highlands. In 1823 there were no less than 1400
prosecutions for such contraventions of the law. Sixty years later the
number had fallen to 22 in consequence not only of the enforcement of the
law, but of the lowering of the spirit duties. The whisky distilled is of
two kinds—malt and grain—according to the method of distilling, and a blend
of both is sold. The increase of 3s. 9d. in the duty per gallon in 1909
affected the production and consumption to a considerable extent and
lessened the number of distilleries at work, which fell from 159 in 1900 to
124 in 1910. Eighty-eight of these were situated in the counties of Banff
and Elgin, Argyle and Inverness. In 1912 the export from the United Kingdom
was about 10 million gallons.
The glassmaking industry is
carried on at Edinburgh and Glasgow. Whilst in the earlier part of the
nineteenth century only bottle glass and flint glass, or crystal, were made
in Scotland, the manufacture of plate or fine mirror glass and other
varieties was gradually introduced. Though the name flint glass is still in
use for crystal, flint has long been superseded by a fine white sand
obtained from the forest of Fontainebleau. The industry was much hampered by
the heavy excise duties levied on glass, which up to 1845 were 56s. per cwt.
for flint glass and 7s. for bottle. With the repeal of these duties in this
year it i materially increased and the value of glass exported from
Scotland, which was £62,140 in 1S61, had risen to £106,555 in 1867. Table
ware formed the bulk of the articles produced and there was comparatively
little competition for the British trade from abroad. But cheaper labour and
superior facilities in the production of table ware in France, Germany, and
Sweden seriously affected the British manufacture during the last quarter of
the nineteenth century. The Continental workmen, moreover, more readily
adopted labour saving appliances than their British fellows, and where these
have been introduced the latter have not shown a disposition to take full
advantage of them. The Holyrood glass works, which were started by Mr Ford
about the beginning of the century, maintained a high reputation throughout
it. They have, however, recently ceased to exist, but the industry is still
carried on by the Messrs Jenkinson at the Norton Park Glass Works, whilst
Messrs Millar & Co. developed a far-famed speciality in glass engraving and
ornamentation. More recently glass engraving has been largely superseded by
etching by means of hydro-fluoric acid, and many improvements in the
machines used in the process have been introduced. Mr Ballantine was a
pioneer in another branch of the industry—that of glass painting—and was
selected by the Fine Arts Commission to execute the windows for the House of
Lords. The firm has produced many of the finest specimens of stained glass
in Scottish churches and other public buildings. Glasgow has also excelled
in the various branches of the industry, especially in the production of all
kinds of globes and shades for gas lights, duplex lamps, and electric light.
The bevelling and silvering of plate glass are also extensively carried on
in the city.
The first pottery in Scotland
was established at Glasgow about the middle of the eighteenth century. Later
in the century Mr Jamieson discovered a rich bed of clay at Portobello and
started a brickwork and pottery, around which grew the village—the nucleus
of the widely-known modern watering place. In the beginning of the
nineteenth the Verreville Pottery was founded at Glasgow and before the
middle of it two more—the Glasgow and the Britannic Potteries—had come into
existence. By the year 1868 the number in Scotland was 14, employing fully
5,000 persons. The materials used in the manufacture -of aarthenware are
imported from the south of England and consist of clays from Dorset and
Devonshire, china clay and Cornish stone from Cornwall, and flints from the
chalk cliffs, which after being rolled about in the Channel are thrown up on
the French coast near Dieppe and exported to this country in large
quantities. These ingredients are mixed in varying proportions according to
the ware to be made and reduced by grinding to a thick cream. The mixture
then passes through sieves, which retain the sand or grit, and this is
thereafter pumped into presses lined with cloth, which retain the clay
whilst allowing the water to exude. It is then put through the pug mill—an
iron cylinder about 5 feet long, in the centre of which is a shaft with
knives attached in spiral fashion—from which the clay emerges thoroughly
solidified and of the same consistency. The introduction of the pug mill has
greatly lightened the potter's labour in the preparation of the clay, and
machinery has in many of the largest potteries done away with the potter's
wheel itself, though there are still many articles which can only be made by
hand. After being shaped in moulds, according to the article to be made, the
clay undergoes the firing or burning process in the "biscuit" kiln. The
decoration of the ware is ordinarily done in the " biscuit " state. The
designs are first engraved on copper plates, from which they are printed on
tissue paper which is applied to the ware and the colour rubbed firmly into
the pores. It then undergoes the glazing process, which is completed in the
glost kiln. Besides ordinary and ornamental ware a large quantity of
sanitary ware is manufactured in the Glasgow potteries, whose output finds
an extensive market in America and the Colonies. Stoneware, fire bricks, and
building bricks are also extensively manufactured at Garnkirk, Glenboig,
Portobello, and other places. |
