PENCIL. 



731 



black lead being nearly halt the price of pure silver, 

 about two guineas per pound. Various shafts are 

 excavated in this mine, some of which appear to 

 be exhausted, which occasions a search for new 

 veins in other directions. One mass was dis- 

 covered in 1803, measuring twenty -one yards and 

 a half in length, and two and a half in diameter. 



The property of this mine is shared between a 

 few individuals, and to show its great value, Mr 

 Parkes states that in sixteen years, from 1798 to 

 1814, 2552 casks, of one hundred and twelve pounds 

 each, weie procured from this mine : of which 736 

 were fine, and 1816 coarse. This we shall find to 

 give an average, one year with another, of 17,864 

 Ibs. ; indeed, the nett profits have been known to 

 be between 20 and 30,000 in one year. The 

 reason why this mine is so particularly valuable, 

 is to be found in the circumstance that the ore re- 

 quires scarcely any labour to fit it for the market, 

 it being originally almost in a pure state. 



Perhaps one of the most remarkable circum- 

 stances connected with plumbago is the mode in 

 which it is sold. After the quantity necessary for 

 supplying the market during the ensuing year is 

 extracted from the mine, and the latter closed up, 

 the product is carried in small fragments of about 

 three or four inches long, to London, where it is 

 exposed for sale at the black lead market, which is 

 held on the first Monday of every month, at a pub- 

 lic house in Essex street, Strand. The buyers, 

 who amount to about seven or eight individuals, 

 examine every piece with a sharp instrument to as- 

 certain its hardness, those which are too soft being 

 rejected. The individual who has the first choice 

 pays forty-five shillings per pound, the others thirty 

 shillings. But as there is no addition made to the 

 first quantity in the market during the course of 

 the year, the residual portions are examined over 

 and over again, until they are exhausted. 



Thus much for the black-lead. The wooden 

 case or exterior of black-lead pencils is usually 

 made of cedar. Of cedar-trees there are many 

 varieties, but the red cedar used for pencils is the 

 Virginian cedar, (Juniperus Viryiniana,*) of North 

 America. 



To prepare the cedar for the pencils, it is cut by 

 a circular saw into four-sided strips of a proper 

 length, and are so arranged as to thickness that two 

 of them together form a square of which one piece is 

 thicker than the other, so as to admit the groove 

 cut to receive the lead, to be confined to one piece 

 only this groove being made by a common plough 

 plane. 



The lumps of plumbago are cut into slices about 

 the thickness of a shilling, by a thin circular saw ; 

 the slices being of various sizes, from one to two 

 inches long, and varying in breadth. 



In preparing the cylindrical leads for the "patent" 

 pencil cases, for which Mr Mordan took out a pa- 

 tent, the plumbago slices are cut into square prisms 

 a little larger than are ultimately required ; and 

 these prisms are brought to the desired cylindrical 

 form by a gradual process of change, produced by 

 an ingenious contrivance. A series of three dif- 

 ferent sized circular holes are cut in pieces of ruby ; 

 the first of which is of such a size as to convert 

 the square prism of black lead into an eight-sided 

 prism, by cutting off the sharp edge : this eight- 

 sided prism is then converted into one of sixteen 

 sides, by thrusting it through the next smaller hole : 

 and lastly, the cylindrical form is given by the third 

 hole which is just the size required. The manner 



of thrusting out the lead in a " Mordan's" pencil 

 case with a little pin inside, will give a good idea 

 of the action of the wire and tube in the above 

 process. 



The rubies are worn out in three or four days. 

 Steel does not last above as many hours. So that 

 the ever-pointed pencils are necessarily costly, six 

 of them being sold for 2s. 6d. If they are cheaper 

 than this we may be sure that they are adulterated. 

 In Paris, when you buy a sheet of paper in a 

 stationer's shop, some of these pencils are added 

 to the purchase. Now these are formed of a mix- 

 ture of plumbago, fuller's earth and vermicelli. 



There is no patent which has been more infringed 

 on than that of Mordan's, for ever-pointed pencils. 

 Birmingham is the source of this infringement, 

 where they are sold as low as three farthings each, 

 formed of composition. A thousand persons are 

 now engaged in the manufacture of these pencils 

 and cases. 



To return to the cedar pencils: One edge of a 

 slice of plumbago being made straight and even, it 

 is dipped in glue, and inserted into the groove cut 

 in the thicker half of the cedar stick. With a 

 sharp tool a cut is made on each surface of the 

 slice, close to the wood, and the piece can then be 

 broken off, leaving, a little prism of lead in the 

 groove. The straight edge of the slice is again 

 dipped in glue, and inserted at the end of the first 

 piece, and again cut off, till the whole length of 

 the groove is filled. The surface of the wood is 

 then smoothed down level, and the other half is 

 glued on, thus making a square black-lead pencil. 



The square pencil is brought into the cylindrical 

 form by passing it through a hole in an iron or steel 

 puppet of the exact size of the pencil, and forced 

 along by the workman. On the other side of this 

 puppet is a revolving apparatus, which cuts the 

 pencil round; it consists of two guages and u small 

 plane iron, revolving round an open centre. Be- 

 yond this is a cylindrical hole in a steel plate; as 

 soon, therefore, as the first edge of the pencil is 

 cut round, it is forced into this circular hole, and 

 before the workman has lost the means of pushing 

 it forward at the end that is square, the cylindrical 

 end is pushed through the circular hole, so as to 

 enable him to seize it with a pair of wooden nip- 

 pers. It is thus pushed and drawn entirely through, 

 and comes out cylindrical and polished, for the hole 

 being a little smaller than the pencil, the latter is 

 compressed in the act of passing through. 



The pencils usually hawked about the streets of 

 London are made with the powder of black lead, 

 mixed with melted sulphur, and then poured into 

 moulds, which are frequently reeds or rushes. 

 Common carpenter's pencils are formed in this way, 

 and answer well enough for the purposes to which 

 they are applied. This mode, however, relates to 

 those common pencils in which the lead (so called) 

 is unusually thick ; but the most successful attempt 

 at deception is where the pencil has all the out- 

 ward form and semblance of being well made, but 

 where a process of anatomization shows the pur- 

 chaser that the amount of black lead is marvellously 

 small, the central part of the groove being filled 

 with a different substance. In common pencils, 

 gum-arabic and resin are often mixed with the 

 plumbago. 



Genuine cedar pencils must cost at least sixpence 

 each. Pencils of a spurious kind are however, 

 sold as low as 4d. per dozen. The melting or 

 softening of the lead when held in a candle, or ap* 



