Page:EB1911 - Volume 21.djvu/97

Rh .—Richard Fenton, A Historical Tour through Pembrokeshire (London, 1810), Edward Laws, History of Little England beyond Wales (London, 1888); Basil Jones and E. A Freeman, History and Antiquities of St David's (London, 1856), &c.

PEMMICAN, a North American Indian (Cree) word for a meat prepared in such a way as to contain the greatest amount of nourishment in the most compact form. As made by the Indians it was composed of the lean parts of the meat, dried in the sun, and pounded or shredded and mixed into a paste with melted fat. It is flavoured with acid berries. If kept dry it will keep for an indefinite time, and is thus particularly serviceable in arctic or other explorations.

 PEMPHIGUS (Gr. πέμφιξ, a bubble), a skin disease, in which large blebs appear, on a red base, containing clear or yellowish fluid; the blebs occasion much irritation, and when they burst leave raw ulcerated surfaces. The disease is principally known in unhealthy or neglected children. A variety of the malady, pemphigus foliaceous, affects the whole body, and gradually proves fatal. Pemphigus of an acute septicaemic type occurs in butchers or those who handle hides, and a diplococcus has been isolated by William Bullock. The treatment is mainly constitutional, by means of good nourishment, warm baths, local sedatives and tonics. In chronic pemphigus, streptococci have been found in the blebs, and the opsonic index was low to streptococci. Improvement has been known to take place on the injection of a vaccine of streptococci.

 PEN (Lat. penna, a feather, pen), an instrument for writing or for forming lines with an ink or other coloured fluid. The English word, as well as its equivalents in French (plume) and in German (Feder), originally means a wing-feather, but in ancient times the implements used for producing written characters were not quills The earliest writing implement was probably the stilus (Gr. γραφίς), a pointed bodkin of metal, bone or ivory, used for producing incised or engraved letters on boxwood tablets covered with wax. The calamus (Gr. κάλαμος) or arundo, the hollow tubular stalk of grasses growing in marshy lands, vsas the true ancient representative of the modern pen; hollow joints of bamboo were similarly employed.

An early specific allusion to the quill pen occurs in the writings of St Isidore of Seville (early part of the 7th century), but there is no reason to assume that it was not in use at a still more remote date The quills still largely employed among Western communities as writing instruments are obtained principally from the wings of the goose (see ). In 1809 Joseph Bramah devised and patented a machine for cutting up the quill into separate nibs by dividing the barrel into three or even four parts, and cutting these transversely into “ two, three, four and some into five lengths.” Bramah's invention first familiarized the public with the appearance and use of the nib slipped into a holder. In 1818 Charles Watt obtained a patent for gilding and preparing quills and pens, which may be regarded as the precursor of the gold pen. But a more distinct advance was effected in 1822, when J. I. Hawkins and S. Mordan patented the application of horn and tortoise-shell to the formation of pen-nibs, the points of which were rendered durable by small pieces of diamond, ruby or other very hard substance, or by lapping a small piece of thin sheet gold over the end of the tortoise-shell.

Metallic pens, though not unknown in classical times—a bronze pen found at Pompeii is in the Naples Museum—were little used until the 19th century and did not

become common till near the middle of that century. It is recorded that a Birmingham split-ring manufacturer, Samuel Harrison, made a steel pen for Dr Joseph Priestley in 1780. Steel pens made and sold in London by a certain Wise in 1803 were in the form of a tube or barrel, the edges of which met to form the slit, while the sides were cut away as in the case of an ordinary quill. Their price was about five shillings each, and as they were hard, stiff and unsatisfactory instruments they were not in great demand. A metallic pen patented by Bryan Donkin in 1808 was made of two separate parts, flat or nearly so, with the flat sides placed opposite each other to form the slit, or alternatively of one piece, flat and not cylindrical as in the usual form, bent to the proper angle for insertion in the tube which constituted the holder. To John Mitchell probably belongs the credit of introducing machine-made pens, about 1822, and James Perry is believed to have been the first maker of steel slip pens. In 1828 Josiah Mason, who had been associated with Samuel Harrison, in the manufacture of split rings, saw Perry's pens on sale in Birmingham, and after examining them saw his way both to improve and to cheapen the process of making them. He therefore put himself in communication with Perry, and the result was that he began to make barrel pens for him in 1828 and slip pens in 1829. Perry, who did much to popularize the steel pen and bring it into general use, in his patent of 1830 sought to obtain greater flexibility by forming a central hole between the points and the shoulders and by cutting one or more lateral slits on each side of the central slit, and Joseph Gillot, in 1831 described an improvement which consisted in forming elongated points on the nibs of the pens.

The metal used consists of rolled sheets of cast steel of the finest quality made from Swedish charcoal iron. These sheets, after being cut into strips of suitable width, annealed in a muffle furnace and pickled in a bath of dilute sulphuric acid to free the surface from oxidized scale, are rolled between steel rollers till they are reduced to ribbons of an even thickness, about $1/160$ in. From these ribbons the pen blanks are next punched out, and then, after being embossed with the name of the maker or other marks, are pierced with the central perforation and the side or shoulder slits by which flexibility is obtained. After another annealing, the blanks, which up to this point are flat, are “ raised” or rounded between dies into the familiar semi-cylindrical shape. The next process is to harden and temper them by heating them in iron boxes in a muffle-furnace, plunging them in oil, and then heating them over a fire in a rotating cylindrical vessel till their surfaces attain the dull blue tint characteristic of spring-steel elasticity. Subsequently they are “scoured ” in a bath of dilute acid, and polished in a revolving cylinder. The grinding of the points with emery follows, and then the central slit is cut by the aid of two very fine-edged cutters. Finally the pens are again polished, are coloured by being heated over a fire in a revolving cylinder, and in some cases are coated with a varnish of shellac dissolved in alcohol. Birmingham was the first home of the steel-pen industry, and continues its principal centre. The manufacture on a large scale was begun in the United States about 1860 at Camden, N.J., where the Esterbrook Steel Pen Manufacturing Company was incorporated in 1866.

Metals other than steel have frequently been suggested by inventors, those most commonly proposed being gold, silver, zinc, German silver, aluminium and aluminium bronze. Dr W. H. Wollaston, it is recorded, had a gold pen composed of two thin strips of gold tipped with rhodium, apparently made on the principle patented by Donkin in 1808, and Lord Byron used one in 1810. Gold being extremely resistant to corrosion, pens made of it are very durable, but the metal is too soft for the points, which wear quickly unless protected by some harder material. For this purpose iridium is widely employed, by fusing the gold round it with a blowpipe.

Various devices have been adopted in order to increase the time for which a pen can be used without a fresh supply of ink. These fall into two main classes. In one, the form of the nib itself is modified, or some attachment is added, to enlarge the ink capacity; in the other, which is by far the more important, the holder of the pen is utilized as a cistern or reservoir from which ink is supplied to the nib. Pens of the second class, which have the further advantage of being portable, are heard of under the name of “ fountain inkhorns ” or “ fountain pens ” so far back as the beginning of the 18th century, but it was not till a hundred