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They are taken from their everyday environment , partially isolated from others, and comfortably seated in a dark auditorium. The darkness concentrates their attention and prevents comparison of the image on the screen with surrounding objects or people. For a while, spectators live in the world the motion picture unfolds before them. Still, the escape into the world of the film is not complete. Only rarely does the audience react as if the events on the screen are real—for instance, by ducking before an onrushing locomotive in a special three-dimensional effect.

Moreover, such effects are considered to be a relatively low form of the art of motion pictures.

Much more often, viewers expect a film to be truer to certain unwritten conventions than to the real world. Although spectators may sometimes expect exact realism in details of dress or locale, just as often they expect the film to escape from the real world and make them exercise their imagination, a demand made by great works of art in all forms.

The sense of reality most films strive for results from a set of codes, or rules, that are implicitly accepted by viewers and confirmed through habitual filmgoing. The use of brownish lighting, filters, and props, for example, has come to signify the past in films about American life in the early 20th century as in The Godfather [] and Days of Heaven [].

Storytelling codes are even more conspicuous in their manipulation of actual reality to achieve an effect of reality.

Audiences are prepared to skip over huge expanses of time in order to reach the dramatic moments of a story. La battaglia di Algeri ; The Battle of Algiers , for example, begins in a torture chamber where a captured Algerian rebel has just given away the location of his cohorts. In a matter of seconds that location is attacked, and the drive of the search-and-destroy mission pushes the audience to believe in the fantastic speed and precision of the operation.

Furthermore, the audience readily accepts shots from impossible points of view if other aspects of the film signal the shot as real. The speed at which the pieces travel over the singe plates is necessarily considerable and varies with different classes of material. For figured pieces which have an uneven surface, it is obvious that plate or roller singeing would only affect the portions which project most, leaving tie rest untouched.

Coal gas mixed with air is sent under pressure through pipe a into the burners b, b, where the mixture burns with an intense heat. The cloth travels in the direction of the arrows, and in passing over the small nap rollers c comes into contact with the flame four times in succession before leaving the machine.

Gas singeing is also used for plain goods, and being cleaner and under better control has largely replaced plate singeing. At this stage the goods which have been browned on the surface by singeing are ready for the bleaching operations.

A great many innovations have been introduced in recent years in the bleaching of calico, but although it is generally admitted that in point of view of time and economy many of these processes offer considerable advantages, the old process, in which a lime boil precedes the other operations, is still the one which is most largely employed by bleachers in England.

In this, the sequence of operations is the following— Grey Washing. On leaving the machine they are piled in a heap and left over night, when fermentation sets in, which results in the starch being to a large extent hydrolysed and rendered soluble in water. Lime Boil—In this operation, which is also known as bowking Ger. It is of the greatest importance that the goods should be evenly packed, for, if channels or loosely-packed places are left, the liquor circulating through the kier, when boiling is subsequently in progress, will follow the line of least resistance, and the result is an uneven treatment.

Of the numerous forms of kier in use, the injector kier is the one most generally adopted.

This consists of an egg-ended cylindrical vessel constructed of stout boiler plate and shown in sectional elevation in fig. The kier is from 10 to 12 ft. The bottom exit pipe E is covered with a shield-shaped false bottom of boiler plate, or and this is more usual the whole bottom of the kier is covered with large rounded stones from the river bed, the object in either case being simply to provide space for the accumulation of liquor and to prevent the pipe E being blocked.

The cloth is evenly packed up to within about 3 to 4 ft. The manholes are now closed, and steam is turned on at the injector J by opening the valve v.

The effect of this is to suck the liquor through E, and to force it up through pipe P into the top of the kier, where it dashes against the umbrella-shaped shield U and is distributed over the pieces, through which it percolates, until on arriving at E it is again carried to the top of the kier, a continuous circulation being thus effected.

Steam is now turned off, and by opening the valve V the liquor, which is of a dark-brown colour, is forced out by the pressure of the steam it contains. Fig 4. The pieces are now run through a continuous washing machine, which is provided with a plentiful supply of water. The machine, which is shown in fig. The pieces enter the machine at each end, as indicated by the arrows, and pass rapidly through the bowls down to the bottom of the vat over a loose roller, thence between the first pair of guide pegs through the bowls again, and travel thus in a spiral direction until they arrive at the middle of the machine, when they leave at the side opposite to that on which they entered.

The same type of machine is used for liming, chemicking, and souring. For white bleaching the rosin soap is omitted, soda ash alone being employed. It is of the utmost importance that the final washing should be as thorough as possible, in order to completely remove the acid, for if only small quantities of the latter are left in the goods, they are liable to become tender in the subsequent drying, through formation of hydrocellulose. The modern processes of bleaching cotton pieces differ from the one described above, chiefly in that the lime boil is entirely dispensed with, its place being taken by a treatment in the kier with caustic soda or a mixture of caustic soda and soda ash and resin soap.

The best known and probably the most widely practised of these processes is one which was worked out by the late M. Horace Koechlin in conjunction with Sir William Mather, and this differs from the old process not only in the sequence of the operations but also in the construction of the kier. This consists of a horizontal egg-ended cylinder, and is shown in transverse and longitudinal sections in figs.

One of the ends E constitutes a door which can be raised or lowered by means of the power-driven chain C. The goods to be bleached are packed in wagons W outside the kier, and when filled these are pushed home into the kier, so that the pipes p fit with their flanges on to the fixed pipes at the bottom of the kier. The heating is effected by means of steam pipes at the lowest extremity of the kier, while the circulation of the liquor is brought about by means of the centrifugal pump P, which draws the liquor through the pipes p from beneath the false bottoms of the wagons and showers it over distributors D on to the goods.

By this mode of working a considerable economy is effected in point of time, as the kier can be worked almost continuously; for as soon as one lot of goods has been boiled, the wagons are run out and two freshly-packed wagons take their place. The rest of the operations chemicking, souring and washing are the same as in the old process. A somewhat different principle is involved in the Thies-Herzig process. In this the kier is vertical, and the circulation of the liquor is effected by means of a centrifugal or other form of pump, while the heating of the liquor is brought about outside the kier in a separate vessel between the pump and the kier by means of indirect steam.

The sequence of operations is similar to that adopted in the Mather-Koechlin process, differing chiefly from the latter in the first operation, which consists in running the goods, after singeing, through very dilute boiling sulphuric or hydrochloric acid, containing in either case a small proportion of hydrofluoric acid, and then running them through a steam box, the whole operation lasting from twenty to sixty seconds.

The machine consists essentially of a series of copper or tinned iron cylinders, which are geared together so as to run at a uniform speed. The pieces pass in the direction of the arrow fig.

If the bleaching process has been properly conducted, the pieces should not only show a uniform pure white colour, but their strength should remain unimpaired. Careful experiments conducted by the late Mr. Charles O'Neill showed in fact that carefully bleached cotton may actually be stronger than in the unbleached condition, and this result has since been corroborated by others. Excessive blueing, which is frequently resorted to in order to cover the defects of imperfect bleaching, can readily be detected by washing a sample of the material in water, or, better still, in water containing a little ammonia, and then comparing with the original.

The formation of oxycellulose during the bleaching process may either take place in boiling under pressure with lime or caustic soda in consequence of the presence of air in the kier, or through excessive action of bleaching powder, which may either result from the latter not being properly dissolved or being used too strong.

Its detection may be effected by dyeing a sample of the bleached cotton in a cold, very dilute solution of methylene blue for about ten minutes, when any portions of the fabric in which the cellulose has been converted into oxycellulose will assume a darker colour than the rest. The depth of the colour is at the same time an indication of the extent to which such conversion has taken place.

Most bleached cotton contains some oxycellulose, but as long as the formation has not proceeded far enough to cause tendering, its presence is of no importance in white goods. If, on the other hand, the cotton has to be subsequently dyed with direct cotton colours see Dyeing , the presence of oxycellulose may result in uneven dyeing.

Tendering of the pieces, due to insufficient washing after the final souring operation, is a common defect in bleached goods. As a rule the free acid can be detected by extracting the tendered material with distilled water and adding to the extract a drop of methyl orange solution, when the latter will turn pink if free acid be present.

Other defects which may occur in bleached goods are iron stains, mineral oil stains, and defects due to the addition of paraffin wax in the size. Bleaching of Linen. The bleaching of linen is a much more complicated and tedious process than the bleaching of cotton. The methods at present employed for the bleaching of linen are, except in one or two unimportant particulars, the same as were used in the middle of the 19th century. Considerably more care has to be exercised in linen bleaching than is the case with cotton, and the process consequently necessitates a greater amount of manual labour.

The practical result of this is that whereas cotton pieces can be bleached and finished in less than a week, linen pieces require at least six weeks.

Many attempts have naturally been made to shorten and cheapen the process, but without success. The use of stronger reagents and more drastic treatment, which would at first suggest itself, incurs the risk of injury to the fibre, not so much in respect to actual tendering as to the destruction of its characteristic gloss, while if too drastic a treatment is employed at the beginning the colouring matter is liable to become set in the fibre, and it is then almost impossible to remove it.

Jardin seeks to achieve the same object by steeping the linen in dilute nitric acid. Since the qualities of linen which are submitted to the bleacher vary considerably, and the mode of treatment has to be varied accordingly, it is not possible to give more than a bare outline of linen bleaching.

Linen is bleached in the yarn and in the piece. Whenever one of the operations is repeated, the strength of the reagent is successively diminished. In yarn-bleaching the sequence of the operations is about as follows:— 1 Boil in kier with soda ash.

This operation, which is peculiar to linen bleaching, consists in suspending the hanks from a square roller into bleaching powder solution contained in a shallow stone trough. The roller revolves slowly, so that the hanks, while passing continuously through the bleaching powder, are for the greater part of the time being exposed to the air. For a full white, two more operations are usually required, viz. Washing intervenes between all these operations.

Pieces are not stamped as in the case of cotton, but thread-marked by hand with cotton dyed Turkey red. They are then sewn together end to end, and subjected to the following operations:— Boil with lime in kier. The pieces are now separated and made up into bundles except in the case of very light linens, which may pass through the whole of the operations in rope form and soured with sulphuric acid.

First lye boil with soda ash and caustic soda. Second lye boil. For some classes of goods no less than six lye boils may be required. Grass between lye boils according to their number. Rub with rubbing boards. This is also a speciality in linen bleaching, and consists of a mechanical treatment with soft soap, the object of which is to remove black stains in the yarn.

Bleach with hypochlorite of soda. The pieces are next steeped in large vessels kiers in weak hypochlorite of soda, and then in weak sulphuric acid, these treatments being repeated several times. Ultimately the goods are mill-washed, blued with smalt and dried. Bleaching of other Vegetable Textile Fabrics. Hemp may be bleached by a process similar to that used for linen, but this is seldom done owing to the expense entailed.

China grass is bleached like cotton.

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Jute contains in its raw state a considerable amount of colouring matter and intracellular substance. Although it is possible to bleach jute white, this is seldom if ever carried out on a large scale owing to the great expense involved. A half-bleach on jute is obtained by steeping the goods alternately in bleaching powder or hypochlorite of soda and sulphuric acid, washing intervening.

For a cream these treatments are repeated. Bleaching of Straw. In the Luton district, straw is bleached principally in the form of plait, in which form it is imported. The bleaching is effected by steeping the straw for periods varying from twelve hours to several days in fairly strong alkaline peroxide of hydrogen. The number of baths depends upon the quality of straw and the degree of whiteness required.

After bleaching with peroxide and drying, the straw consequently undergoes a further process of sulphuring, i. Panama hats are bleached after making up, but in this case only peroxide of hydrogen is used and a very lengthy treatment entailing sometimes fourteen days' steeping is required.

Bleaching of Wool. In the condition in which it is delivered to the manufacturers wool is generally a very impure article, even if it has been washed on the sheep's back before shearing.

Essential characteristics of motion pictures

In this condition wool is quite unfit for any manufacturing purposes and must be cleansed before any mechanical operations can be commenced.

Formerly the washing was effected in stale urine, which owed its detergent properties mainly to the presence of ammonium carbonate. The finest qualities of wool are washed with soft soap and potash, while for inferior qualities, cheaper detergents are employed. The operation is in principle perfectly simple, the wool being submerged in the warm soap solution, where it is moved about with forks and then taken out and allowed to drain. A second treatment in weaker soap serves to complete the process.

In dealing with large quantities, wool-washing machines are employed, which consist essentially of long cast-iron troughs which contain the soap solution. The wool to be washed is fed in at one end of the machine and is slowly propelled to the other end by means of a system of mechanically-driven forks or rakes.

As it passes from the machine, it is squeezed through a pair of rollers.

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Three such machines are usually required for efficient washing, the first containing the strongest and the third the weakest soap. The washing of wool is in the main a mechanical process, in which the water dissolves out the suint while the soap emulsifies the yolk and thus removes it from the fibre.

The attendant earthy impurities pass mechanically into the surrounding liquid and are swilled away. In some works the wool is washed first with water alone, the aqueous extract thus obtained being evaporated to dryness and the residue calcined.

A very good quality of potash is thus obtained as a by-product. In many works in Yorkshire and elsewhere, the dirty soap liquors obtained in wool-washing are not allowed to run to waste, but are run into tanks and there treated with sulphuric acid. The effect of this treatment is to decompose the soap, and the fatty acids along with the wool-grease rise as a magma to the surface.He was the first to insist upon the value of measurement in science and in medicine, thus replacing theory and guesswork with accuracy.

It's said that he read the entire Encyclopedia Britannica at age nine and would immerse himself in sci-fi novels for more than 10 hours a day. The pieces are now separated and made up into bundles except in the case of very light linens, which may pass through the whole of the operations in rope form and soured with sulphuric acid. It is essential that a thorough circulation of the liquor should be maintained during the boiling, and this is effected either by means of a steam injector, or in other ways.

Furthermore, the audience readily accepts shots from impossible points of view if other aspects of the film signal the shot as real. The practical result of this is that whereas cotton pieces can be bleached and finished in less than a week, linen pieces require at least six weeks. In general, a better approach is the use of aspheric surfaces and fewer elements.