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SIR JOSEPH WHITWORTH

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Originally appearing in Volume V28, Page 617 of the 1911 Encyclopedia Britannica.
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SIR JOSEPH WHITWORTH, Bart. (1803-1887), English engineer, was born at Stockport, near Manchester, on the 21st of December 1803. On leaving school at the age of fourteen, he was placed with an uncle who was a cotton-spinner, with the view of becoming a partner in the business; but his mechanical tastes were not satisfied with this occupation, and in about four years he gave it up. He then spent some time with various machine manufacturers in the neighbourhood of Manchester, and in 1825 moved to London, where he gained more experience in machine shops, including those of Henry Maudslay. In 1833 he returned to Manchester and started in business as a tool-maker. In 1840 he attended the meeting of the British Association at Glasgow, and read a paper on the preparation and value of true planes, describing the method which he had successfully used for making them when at Maudslay's, and which depended on the principle that if any two of three surfaces exactly fit each other, all three must be true planes. The accuracy of workman-ship thus indicated was far ahead of what was contemplated at the time as possible in mechanical engineering, but Whitworth not only proved that it could be attained in practice, but also showed how it could be measured. He found that if two true planes were arranged parallel to each other, an exceedingly small motion towards or from each other was sufficient to determine whether an object placed between them was held firmly or allowed to drop, and by mounting one of the planes on a screwed shaft provided with a comparatively large wheel bearing a scale on its periphery, he was able to obtain a very exact measurement of the amount, however minute, by which the distance between the planes was altered, by observing through what angular distance the wheel had been turned. In 1841, in a paper read before the Institution of Civil Engineers, he urged the necessity for the adoption of a uniform system of screw threads in place of the various heterogeneous pitches then employed. His system of standard gauges was also widely adopted. The principles of exact measurement and workmanship which he advocated were strictly observed in his own manufactory, with the result that in the Exhibition of 1851 he had a show of machine tools which were far ahead of those of any competitor. It was doubt-less this superiority in machine construction that caused the government three years later to request him to design, and estimate for making, the machinery for producing rifled muskets at the new factory at Enfield. He did not see his way to agree to the proposition in this form, but it was ultimately settled that he should undertake the machinery for the barrels only. Finding that there was no established practice to guide him, he began a series of experiments to determine the best principles for the manufacture of rifle barrels and projectiles. He ultimately arrived at a weapon in which the necessary rotation of the projectile was obtained, not by means of grooving, but by making the barrel polygonal in form, with gently rounded angles, the bullets also being polygonal and thus travelling on broad bearing-surf aces along the rotating polygon. The projectile he favoured was 3 to 32 calibres in length, and the bore he fixed on was 0.45 in., which was at first looked upon as too small. It is re-ported that at the trial in 1857 weapons made according to these principles excelled the Enfield weapons in accuracy of fire, penetration and range to a degree " which hardly leaves room for comparison." He also constructed heavy guns on the same lines; these were tried in competition with Armstrong's ordnance in 1864 and 1865, and in their inventor's opinion gave the better results, but they were not adopted by the government. Inconstructing them Whitworth experienced difficulty in getting large steel castings of suitable soundness and ductility, and thus was led about 1870 to devise his compressed steel process, in which the metal is subjected to high pressure while still in the fluid state, and is afterwards forged in hydraulic presses, not by hammers. In 1868 he founded the Whitworth scholarships, setting aside an annual sum of £3000 to be given for " intelligence and proficiency in the theory and practice of mechanics and its cognate sciences," and in the following year he was created a baronet. Ile died at Monte Carlo, whither he had gone for the sake of his health, on the 22nd of January 1887. In addition to handing over £100,000 to the Science and Art Department for the permanent endowment of the thirty Whitworth scholarships, his residuary legatees, in pursuance of what they knew to be his intentions, expended over half a million on charitable and educational objects, mainly in Manchester and the neighbourhood. WHOOPING-COUGH, or HOOPING-COUGH (syn. Pertussis, Chin-cough), a specific infective disease of the respiratory mucous membrane, of microbic origin (see PARASITIC DISEASES), manifesting itself by frequently recurring paroxysms of convulsive coughing accompanied with peculiar sonorous inspirations (or whoops). Although specially a disease of childhood, whooping-cough is by no means limited to that period but may occur at any time of life. It is one of the most dangerous diseases of infancy, the yearly death-rate in England and Wales for each of the five years 1904-1908 being greater than that from scarlet fever and typhoid added together. The majority of these deaths were in infants under one year, 97% in children under 5 years (Tatham). It is more common in female than in male children. There is a distinct period of incubation variously estimated at from two to ten days. Three stages of the disease are recognized, viz. (1) the catarrhal stage, (2) the spasmodic or paroxysmal stage, (3) the stage of decline. The first stage is characterized by the ordinary phenomena of a catarrh, with sneezing, watering of the eyes, irritation of the throat, feverishness and cough, but in general there is nothing in the symptoms to indicate that they are to develop into whooping-cough, but the presence of an ulcer on the fraenum linguae is said to he diagnostic. The catarrhal stage usually lasts from ten to fourteen days. The second stage is marked by the abatement of the catarrhal symptoms, but at the same time by increase in the cough, which now occurs in irregular paroxysms both by day and by night. Each paroxysm consists in a series of violent and rapid expiratory coughs, succeeded by a loud sonorous or crowing inspiration—the " whoop" During the coughing efforts the air is driven with great force out of the lungs, and as none can enter the chest the symptoms of impending asphyxia appear. The patient grows deep-red or livid in the face, the eyes appear as if they would burst from their sockets, and suffocation seems imminent till relief is brought by the " whoop " --the louder and more vigorous the better. Occasionally blood bursts from the nose, mouth and ears, or is extravasated into the conjunctiva of the eyes. A single fit rarely lasts beyond from half to three-quarters of a minute, but after the " whoop " another recurs, and of these a number may come and go for several minutes. The paroxysm ends by the coughing or vomiting up of a viscid tenacious secretion, and usually after this the patient seems comparatively well, or, it may be, somewhat wearied and fretful. The frequency of the paroxysms varies according to the severity of the case, being in some instances only to the extent of one or two in the whole day, while in others there may be several in the course of a single hour. Slight causes serve to bring on the fits of coughing, such as the acts of swallowing, talking, laughing, crying, &c., or they may occur without any apparent exciting cause. In general children come to recognize an impending attack by a feeling of tickling in the throat, and they cling with dread to their mothers or nurses, or take hold of some object near them for support during the paroxysm; but although exhausted by the severe fit of coughing they soon resume their play, apparently little the worse. The attacks are on the whole most severe at night. This stage of the disease usually continues for thirty to fifty days, but it may be shorter or longer. It is during this time that complications are apt to arise which may become a source of danger greater even than the malady itself. The chief of these are inflammatory affections of the bronchi and lungs and convulsions, any of which may prove fatal. When, however, the disease progresses favourably, the third or terminal stage is announced by the less frequent paroxysms of the cough, which generally loses in great measure its " whooping " character. The patient's condition altogether undergoes amendment, and the symptoms disappear in from one to three weeks. It is to be observed, however, that for a long period afterwards in any simple catarrh from which the patient suffers the cough often assumes a spasmodic character, which may suggest the erroneous notion that a relapse of the whooping-cough has occurred. In severe cases it occasionally happens that the disease leaves behind it such structural changes in the lungs (emphysema, &c.), as entail permanent shortness of breathing or a liability to attacks of asthma. Further, whooping-cough is well known to he one of those diseases of early life which are apt to give rise to a weakened and vulnerable state of the general health, or to call into activity any inherited morbid tendency, such as that towards consumption. As regards the treatment in mild cases, little is necessary beyond keeping the patient warm and carefully attending to the general health. The remedies applicable in the case of catarrh or the milder forms of bronchitis are of service here, while gentle counter-irritation to the chest by stimulating liniments may be employed all through the attack. In mild weather the patient may be in the open air. An abdominal binder shculd be worn night and day in order to prevent the occurrence of hernia. Systematic disinfection of the sputum by means of a solution of corrosive sublimate or by burning should be practised in order to check the spread of infection. In the more severe forms efforts have to be employed to modify the severity of the paroxysms. Numerous remedies are recommended, the chief of which are the bromides of ammonium or potassium, chloral, codeine, &c. These can only be safely administered under medical advice, and with due regard to the symptoms in individual cases. During convalescence, where the cough still continues to be troublesome, a change of air will often effect its removal.
End of Article: SIR JOSEPH WHITWORTH
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