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merly very extensively employed as a substitute Numerous other plant tissues have from for Manila.
time to time been suggested, used and dis
used for paper-making, and some are still in ADANSONIA.
use for special purposes. Various kinds of Adansonia, the bast of the monkey bread
reeds, the China grass, sun hemp, hey, and tree (Adansonia digitata L.) of West Africa, is
potato husks may be mentioned in this conused for manifold purposes by the natives, and
nection. forms the raw material for a paper-making fibre remarkable for its strength and tough
BROKE. ness ; Adansonia papers show a resistance to | “Broke " paper is of considerably more tearing not unlike that of the Japanese papers. importance than some of the foregoing as It is much to be regretted that this valuable
a paper - making material ; it includes material is only obtainable in very limited
paper which has been used and printed quantities.
upon and which finally finds its way back FLAX WASTE.
into the mill, and also the spoilt paper, The waste from flax is used in some mills as
which has always to be rejected when a
paper machine is started or when the paper a cheap substitute for hemp and Manila hemp
during its journey on the machine accidentally in the manufacture of brown wrapping papers.
breaks. The“ broke" is divided into various Manila hemp, jute, adansonia, and flax waste,
qualities, according to the composition and are boiled either with lime or with caustic soda
state of purity, and according to whether the as described under straw and esparto, accord
paper is white or printed upon. The treating to the purpose for which they are intended.
ment has, therefore, to be chosen accord. The yield obtained with lime is better than
ing to the quality. In order to free the that given by soda, but the colour of the pulp
paper from greasy matter and printing ink, is inferior. The bleaching of these fibres is
it is first of all boiled-usually with soda always attended with difficulties and a re
lye-in open or revolving boilers. Papers petition of the treatment with bleaching liquor is often found necessary to obtain a satis
which have been printed upon were previously factory white colour.
worked up into inferior qualities on account of
the impossibility of effectively removing the Peat.
printing ink, but Knopf has patented a process As early as 1765 Schäffer tried to use peat
by means of which the ink is successfully refor paper-making and samples of papers made
moved by treating the paper with soap solutions. partly from peat are contained in Louis Piette's
The broke paper produced during manufacture book, “ Die Fabrikation des Papieres," pub
requires little or no treatment if it is still in a
moist condition, and in many cases it may be lished in 1861. Since that time attempts have been made to use peat in the manufacture of
thrown back into the beater; if dried, howpaper, but without satisfactory results. During
ever, a slight boiling may be found necessary the last few years, however, more promising
for the purpose of removiug the size. The results have been obtained owing to a special
fibres in “ broke,” being already in a sufficiently method of disintegration by means of which
disintegrated condition, require no further the fibres are separated without their strength
beating, and passing through one of the
various types of “ stuff squeezers," such as being diminished.
Wurster-Voith's (Figs. 10 and 1) or Simonet's, SORGHUM AND SUGAR-CANE.
or grinding in an “edge runner " (Kollergang) From both of the above materials useful is generally found sufficient treatment. paper-making fibres may be prepared, and
MECHANICAL Wood Pulp. they are used in places where easily obtainable.
Although Schäffer and others before him had BAMBOO.
tried to employ wood as a paper-making raw Thomas Routledge, during and after 1870, material, Matthias Koops is the first who used made very extensive experiments with the wood in a practical manner. In two copies of object of introducing this excellent paper. his book in my possession, now over 100 years making fibre, so extensively used by the old, which are both partly printed on paper Chinese, into this country; he did not, how made from wood, the leaves are in a state of ever, succeed in obtaining satisfactorily perfect preservation. All that may be justly practical results.
urged against the use of wood as a paper
making raw material is, without doubt, by far the manufacture of news and cheap papers outweighed by the vast benefit which we have generally; it possesses hardly any felting derived from its introduction. F. G. Keller, a properties, and admixture with other fibres, weaver, born in Haynichen, in Saxony, in the such as wood cellulose, is therefore absolutely year 1816, is the inventor of mechanical wood necessary, to impart to the paper the necessary pulp; in 1840 he commenced a series of strength. successful experiments on this subject. Keller entered into an agreement with Voelter, but
MANUFACTURE OF MECHANICAL WOOD by 1846 had practically lost his share
PULP. in the invention. The further working | Carefully selected wood is freed from the out and the introduction of the process bark, from knots and from all such portions after this date are due to Voelter, and Keller | as might have a detrimental influence on received only a few pounds as his share. the quality of the pulp, by means of special In 1892 he appealed to the paper-makers for boring and other machines. The next operahelp, and it is of interest to state that-accord- i tion consists in the grinding of the wood, and
ing to Hofmann, who gives a full account of the apparatus employed varies in construction Keller's life in his standard work on paper in the different mills. making-a collection made in various countries A large cylindrical sandstone, revolving realised the sum of about £1,000, to which either horizontally or vertically, forms the the paper-makers of this country contributed essential part of the grinding arrangement: about £22.
the cylindrical surface of the stone is roughened The pulp obtained by the disintegration of and grooved so as to present a large grinding wood by mechanical means only, is called surface. The wood blocks are steadily pressed " mechanical wood pulp.” The various species against the surface of the stone by means of of pine-wood-Pinus picea, Pinusabies, Pinus screws or, in more modern mills, by means of Sylvestris-form the principal raw materials | hydraulic presses. A continuous stream of for this product. The pulp obtained from water is directed between the blocks, thus Pinus picea possesses the best paper-making preventing overheating of the wood, the water qualities. Poplar, aspen, birch, linden, beech, serving at the same time to carry away the maple, and other woods are also used, though ground wood. on a less extensive scale. Mechanical wood A passage through a sorter, which consists pulp constitutes the principal raw material in l of a series of frames (the upper one being
covered with a very coarse wire gauze, whilst by means of a special disintegrator and then in the lower ones the size of the mesh is thrown into the beater. gradually diminished), divides the pulp into various grades. The coarsest pulp is passed
BROWN MECHANICAL WOOD. through an apparatus called the “refiner," which resembles a pair of millstones such as Brown mechanical wood is a fibrous mate. are used in a flour mill. Although uniformity of rial which is practically intermediate in pulp is obtained by this treatment the disin- character between mechanical wood pulp and tegration, if carried too far, results in com- wood cellulose ; it was first prepared in 1868 plete destruction of the fibrous nature of the by Moritz Behrend in Prince Bismarck's paper pulp.
mills in Varzin. Although considerably · The final operation is the conversion of the darker in colour than the ordinary mechanical pulp into boards, and this is accomplished wood, this material is of a more fibrous nature on a “board machine."
and therefore possesses superior felting proIn this machine, a slowly revolving drum, perties. It is extensively used as a substitute
covered with wire gauze, is placed in a vat for hemp and jute in the manufacture of cheap to which the pulp from the sorters, mixed with brown wrappings. the necessary quantity of water, is conducted. The pulp, which deposits itself on the wire, is
CHEMICAL WOOD PULP OR Wood removed by means of a felt ; it is further freed
CELLULOSE. from water by pressing between rollers, and So-called “wood cellulose” or “chemical finally wound round a cylinder, from which it wood pulp” is distinctly different in action is cut off as soon as the sheet has reached a from mechanical wood pulp, and is precertain thickness.
pared by subjecting wood to a chemical Mechanical wood pulp may be bleached by treatment; of the numerous processes for its the use of a solution of either sodium or calcium manufacture which have been discovered and bisulphite. Wood pulp, if purchased in a patented, but few have found technical applimoist condition, may be fed into the beater cation. I will only mention the processes of without any previous treatment, but if the Watt-Burgess (1853), and of Houghton (1857), pulp has been dried the dry boards first must in which wood is treated with aqueous solutions be soaked in hot water and then ground in an of alkalis, Jullion's (1855), Blitz's (1883), and edge runner, or must be torn into small pieces | Dahl's (1884) processes, in which alkaline
sulphides are used, and lastly, those devised by stronger pulp is, however, obtained by the Tilghmann (1866), Mitscherlich (1874), Ekman sulphate process. (1881), Francke (1881), and Graham (1882), The Sulphite Processes.-The use of liquid in which bisulphites are the chemical agents sulphurous acid proposed by Pictet has for employed for the disintegration of the wood. various reasons found ng practical application. The wood cellulose is called “soda wood," Tilghman, in his patents of 1866 and 1867, “ sulphate wood,” or “sulphite wood,” ac describes the use of aqueous solutions of sulcording to the particular type of process which phurous acid for the manufacture of cellulose has been used in its manufacture. The fibres from wood and other fibrous materials. of chemical wood are, practically speaking, As early as 1874 Ekman applied magnesium pure cellulose, they possess excellent felting bisulphite, whilst the credit of having introproperties, and may be readily bleached. | duced the cheaper calcium bisulphite for this Wood cellulose may be counted among the purpose is due to Dr. A. Mitscherlich, who, best substitutes for rags, and its application according to Hofmann, produced cellulose on has become so general that it would be a commercial scale by means of this process in difficult to name the kinds of papers to which 1874. To ensure uniform resolution of the its use is confined. In “news” and other ligno - celluloses it is essential to chip the cheap papers it acts as a binding agent to wood, after it has been freed from bark and hold the mechanical wood together; in “writ. | knots, into small pieces and to pass these ings” and “printings” it is necessary to | through crushing rollers and sorters. The blend it suitably with other fibres, such as boiling liquor, which consists of a solution of straw, cotton, &c., in order to overcome its either calcium or magnesium bisulphite, is transparency. This latter property, however, prepared by the action of sulphur dioxide on has made the wood cellulose a most valuable calcium or magnesium carbonate or on an material for the manufacture of imitation parch- aqueous solution of calcium or magnesium ment and of “butter," “ grease proof," and oxide respectively in water. tracing papers. Papers made from wood 1 For the preparation of the sulphur dioxide cellulose are closely felted and of a uniform required, sulphur is burned, or pyrites are appearance, they take an excellent finish and roasted in specially - designed ovens which colour, present a good smooth surface, and are supplied with such a quantity of air as have a good feel.
contains the amount of oxygen required to The manufacture of wood cellulose has form sulphur dioxide. After leaving the oven, developed into an enormous industry, and the gas is cooled and washed. Large towers although the description of details lies outside | are used for the preparation of the bisulphite the scope of these lectures, I will endeavour to liquor from either limestone or from dolomite sketch the outlines of the various typical (magnesia limestone); these are filled with processess in use at the present time. In the the stone, and a continuous stream of water is soda process, the wood, freed from bark, knots, allowed to flow downwards whilst the sulphur &c., is cut into pieces of suitable size, and is dioxide enters the tower from below. The usually boiled in vertical stationary boilers bisulphite liquor, prepared by this method, with caustic sodalye, under high pressure | flows into a tank placed at the bottom of the (60 to 150 lbs. per square inch). The boiling tower. is followed by a preliminary washing in the
. The other method of preparing bisulphite boiler, and the washing and bleaching of the liquor consists in passing sulphur dioxide into pulp are generally completed in the Hollander, milk of lime contained in closed vessels profrom which the pulp is transferred to a cylinder
vided with stirrers; the gas passes through a machine and converted into boards. The soda series of these vessels in succession, and the lye from the boiling, as well as the first wash operation is so conducted as to ensure comwater, are subsequently dealt with in the soda plete absorption of the dioxide, whilst the recovery plant, as described under straw. atmospheric nitrogen escapes from the last
The Sulphate Processes. The sulphate | vessel. processes, in which sodium sulphate and The three principal forms of boilers, the caustic soda are primarily employed as boil. upright stationary, the cylindrical, and the ing agents, differ generally speaking in spherical rotary, are used as digesters in the minor details only from the alkali processes, manufacture of sulphite cellulose, but to protect the construction of the plant and the treatment the metal against the destructive action of the being in the main similar. A superior and acid it is found necessary to line the boilers
with an acid-resisting material. Lead was with in its unceasing missionary efforts in the cause of formerly used for this purpose, but has now scientific instruction. I shall not attempt to do more been superseded by more serviceable materials, than show that whatever its defect may have been in such as Wenge's composition consisting of
tact, whatever its shortcomings in method, that Portland cement and sodium silicate-Kellner's
Department still deserved well of the country for the composition-cement, with ground slate or glass,
work that it did in regard to the fostering of scientific and many others.
instruction in the country at large. The time of boiling, the strength of the
As far back as 1852 the Government of the day,
influenced very largely by the Prince Consort, realised liquor used, and the pressure, vary consider
that it had an educational duty to perform to the ably in the different works; whilst in some in
industrial classes. Whether it was influenced by stances the wood is digested during three days philanthropic motives or from the evidence before it at a pressure of 45 lbs. per square inch, in that if Great Britain was to maintain its commercial others, the treatment is completed in one day, and industrial supremacy scientific instruction was a at a pressure of 90 to 100 lbs. The wood, as it necessity, it matters little. The fact remains that it comes from the digester, is still further treated determined that the industrial classes should have an in order to bring about a complete separation opportunity of acquiring that particular kind of knowof the fibres, and the pulp is finally washed and ledge which would be of service to them as craftsbleached in the ordinary breaker. In the
men. In this year, 1852, the Speech from the Throne bleaching of sulphite wood a difficulty often
contained these words : “ The advancement of Fine
Arts and of Practical Science will be readily recogpresents itself in the appearance of a reddish
nised by you as worthy of a great and enlightened brown colour, which strongly resists the action of the bleaching liquor ; this may be readily
nation. I have directed that a comprehensive scheme
shall be laid before you, having in view the promotion avoided by treating the pulp with a solution of
of those objects towards which I invite your aid and caustic soda or sodium carbonate as a pre
co-operation." liminary to the actual bleaching.
It is somewhat remarkable that the then Ministry, of which Lord Derby was the chief and Mr. Disraeli the Chancellor of the Exchequer, did not survive to
promulgate the scheme, which proposed theoretical Miscellaneous.
rather than practical science, but that their successors, under Lord Aberdeen, issued it and commenced to
carry it into effect. In 1853 the Department of SCIENTIFIC INSTRUCTION.*
Science and Art was established under the direction The Section over which I have the honour to pre of Mr. Cole. Since 1835 so-called Schools of Design side deals with every branch of education. It is had been in being. These came under the new Demanifest that in an address your President cannot deal partment, and it was determined to establish science with all of them, and it remained for me to choose classes for instruction in science, Dr. Lyon Playfair, one on which I migut remark with advantage. As the well-known chemist, being charged with the duty. my official work during the last thirty-three years has | Playfair resigned in 1858, and in 1859, Mr. Cole inbeen connected with education in science, I think I duced a young Engineer officer, Lieut. Donnelly, to cannot do better than take as my subject the action undertake the inspection and organisation of science that the State has taken in encouraging this form of instruction throughout the country. It was through education, and to show that through such action there this officer's untiring energy and zeal that the classes has been a development of scientific instruction in science flourished and were added to at this early amongst the artisan population and in secondary day stage of the new Department's history. The same schools. The development may not indeed have been energy was displayed by Donnelly during the whole of to the extent hoped for, but it yet remains that solid his long career in the service of the State, and I feel progress has been made.
that it was fortunate for myself to have served so many I have chosen the subject deliberately, as I find years as I did under one to whom the country at large that there are very few of those who have the interests owes a deep debt of gratitude. of education strongly at heart, or who freely criticise Not long ago he passed away from us, and there those who have borne the burden of the past, that will be no more lasting memorial to him than that have any knowledge of the trials and difficulties (some which he himself erected during his lifetime in the of its own creating, but others forced on it by public fostering that form of education which is of such vital opinion) which the State, as represented by the now importance to the national well-being. defunct Science and Art Department, had to contend To revert to history, I may record that the first
science examinations conducted by the State took • From the Address to the Educational Science Section of the British Association, by Sir William de W. Abney,
place in May, 1861, and the system of grants being K.C.B., D.C.L., D.Sc., F.R.S., President of the Section.
made on the results of examination having been (Southport, 1904.)
authorised, the magnificent sum of £1,300 was spent