1050 ULTRAMARINE 



on each side, and turning them with their faces downwards, cuts a groove or channel in 

 their bottom, to make them stand steadily on end. It is essential that each letter be 

 perfectly symmetrical and square : the least inequality of their length would prevent 

 them from making a fair impression ; and were there the least obliquity in their sides, 

 it would be quite impossible, when 200,000 single letters are combined, as in one side 

 of The Times newspaper, that they could hold together as they require to do, when 

 wedged up in the chases, as securely as if that side of the type formed a solid plato 

 of metal. Each letter is finally tied up in lines of convenient length, the pro- 

 portionate numbers of each variety, small letters, points, large capitals, small capitals, 

 and figures, being selected, when the fount of type is ready for delivery to the printer. 

 The sizes of types cast in this country vary, from the smallest, called Diamond, of 

 which 205 lines are contained in a foot length, to those letters employed in placards, 

 of which a single letter may be several inches high. The names of the different 

 letters and their dimensions, or the number of lines which each occupies in a foot, are 

 stated in the following table: 



Double Pica . 41i 



Paragon . . 44 



Great Primer . 51 



English . . 64 



Pica . . . 71 



Small Pica . . 83 



Long Primer . . 89 



Bourgeois . . 102J 



Brevier . . .112.} 



Minion . . 128 



Nonpareil . . M3 



Pearl . . 178 



Diamond . . 205 



TYPE AXETAXi. An alloy of 3 parts of lead and 1 of antimony. Small type, 

 however, usually contains tin, in proportions varying from 1 J to 20 per cent. 



TYRIAltf PURPLE. A costly dye obtained from a mollusc, which was employed 

 by the Tyrians in dyeing wool. See Crookes's ' Handbook of Dyeing.' 



TYRITE. A Norwegian mineral, containing columbic acid and yttria, discovered 

 and analysed by David Forbes. 



TYROI.IItfE. See ANILIXK VIOLET. 



TYROHTE. An arsenate of copper found in the Tyrol. 



TYROSIETE. 



u 



UIiEXITE. A native borate of lime and soda, known also as Boronatrocalcitc. 

 It occurs at Iquique, in Peru ; and in the Province of Tarapaca. See BORON. 



TJIiIiMANNITE. An antimonio-sulphide of nickel, occasionally containing 

 arsenic. It occurs at Freusberg, in Nassau. 



ULTRAIVIARINE (Outremer, Fr. ; Ultramarin, Ger.), is a beautiful blue pig- 

 ment, obtained from the blue mineral called lapis-lasnli, by the following process: 

 Grind the stone to fragments, rejecting all the colourless bits, calcine at a red heat, 

 quench in water, and then grind to an impalpable powder along with water, in a mill, 

 or with a porphyry slab and muller. The paste being dried, is to be rubbed to 

 powder, and passed through a silk sieve. 100 parts of it are to be mixed with 40 of 

 resin, 20 of white wax, 25 of linseed oil, and 15 of Burgundy pitch, previously 

 melted together. This resinous compound is to be poured hot into cold water ; 

 kneaded well first with two spatulas, then with the hands, and then formed into one 

 or more small rolls. Some persons prescribe leaving these pieces in the water during 

 fifteen days, and then kneading them in it, whereby they give out the blue pigment, 

 apparently because the ultramarine matter adheres less strongly than the gangue, or 

 merely siliceous matter of the mineral, to the resinous paste. MM. Clement and 

 Desormes, who were the first to divine the true nature of this pigment, thought that the 

 soda contained in the lapis-lazuli, uniting with the oil and the resin, forms a species of 

 soap, which serves to wash out the colouring-matter. If it should not separate 

 readily, water heated to about 150 Fahr. should be had recourse to. When the water 

 is sufficiently charged with blue colour, it is poured off and replaced by fresh water ; 

 and the kneading and change of water are repeated till the whole of the colour is 

 extracted. Others knead the mixed resinous mass under a slender stream of water, 

 which runs off with the colour into a large earthen pan. The first waters afford, by 

 rest, a deposit of the finest ultramarine; the second a somewhat inferior article, and 

 so on. Each must be washed afterwards with several more waters before they ac- 

 quire the highest quality of tone ; then dried sepirately, and freed from any adhering 

 particles of the pitchy compound by digestion in alcohol. The remainder of the mass 

 being melted with oil and kneaded in water containing a little soda or potash, yields 



