forward will be thus made to pass through the corresponding apertures of the punch- 

 holder g, and by this means will project the punches out of these apertures, into cor- 

 responding apertures of the punch-receiver h. The punches will now be properly 

 arranged for piercing the required holes on a card or slip, which is to be effected in 

 the following manner : 



Remove the punch-receivers from the front of the machine ; and having placed one 

 of the slips of card or pasteboard between the two folding plates of metal, completely 

 pierced with holes corresponding to the needles of the loom, lay the punch-receiver 

 upon those perforated plates ; to which it must be made to fit by mortises and blocks, 

 the cutting parts of the punches being downwards. Upon the back of the punch- 

 receiver is then to be placed a plate or block, studded with perpendicular pins, corre- 

 sponding to the above described holes, into which the pins will fall. The plates and 

 the blocks thus laid together, are to be placed under a press, by which means the pins 

 of the blocks will be made to pass through the apertures of the punch-receiver ; and 

 wherever the punch has been deposited in the receiver by the above process, the said 

 punches will be forced through the slip of pasteboard, and pierced with such holes as 

 are required for producing the figured design in the loom. 



Each card teing thus pierced, the punch-receiver is returned to its place in front of 

 the machine, and all the punches forced back again into the apertures of the punch- 

 holder as at first. The next sort of cords is now drawn forward by the next beard, 

 as above described, which sends out the punch-projectors as before, and disposes the 

 punches in the punch-receiver, ready for the operation of piercing the next card. The 

 process being thus repeated, the whole pattern is by a number of operations, transferred 

 to the punches, and afterwards to the cards or slips, as above described. 



JACYUTH. See JACINTH HYACINTH. 



JADE. Under the common name of Jade two or three distinct minerals, re- 

 sembling one another in many of their physical characters, but differing in chemical 

 composition, are popularly confounded. The true jade, or nephrite, is an anhydrous 

 silicate of lime and magnesia, related to the non-aluminous varieties of hornblende. 

 Jadeite is a mineral closely resembling true nephrite in external characters, but dis- 

 tinguished as a separate species by Damour, whose analyses show that it is essentially 

 a silicate of alumina and soda. A third mineral, originally described by H. B. de 

 Saussure as a jade, was termed Saussurite by T. de Saussure : this was the jade tenace 

 of Haiiy and the early French mineralogists. It is mainly a silicate of alumina and 

 lime, and may be classed with the species termed zoisite. The differences in com- 

 position between the several minerals comprehended under the general name of jade 

 are shown in the following selected analyses : 



It may be useful to give the means of discriminating these minerals by their 

 behaviour before the blowpipe. Nephrite is difficult of fusion, does not colour the 

 flame, but when moistened with solution of nitrate of cobalt assumes a rose colour, 

 due to the presence of magnesia ; Jadeite is readily fusible to a transparent glass, and 

 gives with cobalt a blue colour, due to the alumina ; Saussurite is more fusible than 

 nephrite, but less so than jadeite, it colours the flame blue, and becomes blue with 

 cobalt. 



None of the varieties of jade have been found crystallised, but they usually occur 



