1871.] Technology. 129 



TECHNOLOGY. 



To separate or distinguish the fibres of silk, wool, cotton, jute, &c, when 

 interwoven or composing the structure of mixed fabrics, Mr. Spiller employs 

 concentrated hydrochloric acid, which has the property of dissolving silk 

 immediately and completely, without appreciably affecting any woollen or lignine 

 fibres (cotton, linen, jute, &c.) with which the silk may have been interwoven. 

 Having submitted the material to the a&ion of hydrochloric acid and noted any 

 indications of rupture or solution of the fibres, the residual fabric or loose fila- 

 ments may be washed and collected, and will usually be destitute of colour. 

 The presence or absence of wool in that portion of the fabric which resists the 

 attack of hydrochloric acid is then determined. A warm aqueous solution of 

 picric acid instantly imparts a full yellow tint to wool, but does not in the least 

 affect cotton, linen, jute, or China grass, so that it is only necessary to immerse 

 the fabric or fibres in the dye, wring out, and wash well with water in order to 

 remove the adhering yellow solution, and note any indications of the existence 

 of wool. In the examination of ribbons and some other stiffened goods it is 

 often necessary to immerse them for a few minutes in boiling water, to dissolve 

 out the starch or size prior to applying the hydrochloric acid test, for, by this 

 simple expedient, the results are rendered much more decisive. 



A new sulphur deposit has been discovered in the Island of Saba, a Nether- 

 lands' possession; it was accidentally discovered by an enterprising New 

 Yorker, who visited the island in search of health. With the aid of some of 

 the natives, he succeeded in quarrying about two sloop-loads of the crude 

 mineral, which, on being brought to New York, was found to yield, on an 

 average, rather over 60 per cent of sulphur, while the Sicily mineral only 

 yields about 30 per cent. The deposit is, considering the small size of the 

 island, very extensive, and will be of great value for the manufacturing interests 

 of the United States, being distant only about 1500 miles from New York. 



When glue, in thick solution, is mixed with tungstate of soda, and hydro- 

 chloric acid is added, there is thrown down a compound of tungstic acid and 

 glue, which, at from 30 to 40 C. is so elastic as to admit of being drawn out 

 into very thin sheets. On cooling, the mass becomes solid and brittle; but, on 

 being heated, it becomes again soft and plastic. This material has been suc- 

 cessfully employed, instead of albumen, in calico-printing, in order to fix the 

 aniline colours upon cotton. 



M. Mene has effected some considerable improvements in the treatment of 

 wood for paper manufacture. The wood, previously reduced to the state of 

 shavings or sawdust, is placed for a time in water, and is left there to rest. 

 The rotting in water has the effect of disintegrating and partly decomposing 

 the nitrogenous matter of the wood, and the fibre is also afterwards more 

 readily bleached, not becoming yellow by the use of chlorine, as is the case 

 where these matters have been left in the wood. The rotted wood is tho- 

 roughly washed with boiling water and steamed, and next treated with an alkali. 



Experiments with gun-cotton have recently been made at Chatham on an 

 unprecedented scale of magnitude, and in connection with a 

 system of electric-torpedo defence. Charges of 432 lbs. weight Fig. 32. 

 have, upon two separate occasions, been fired by Messrs. Abel 

 and Brown, with results which are stated in the official reports 

 to be of the most decisive character, and such as would un- 

 doubtedly have sent to the bottom the largest iron-clad vessel 

 in the world, had she been within range. 



There are many locations in which the Bunsen filter pump 

 cannot be employed on account of a deficiency in the water 

 supply. For such cases a plan has been devised by Dr. Walz, 

 of New York, which has been proved in practice to be efficient. 

 The accompanying cut shows the outline se&ion of the most 

 important part of the apparatus, a is a tube supplied with 

 steam from a flask or boiler; e is connected with the ex- 

 haust of the filter. By the action of the steam jet identical 

 with that known as the " exhaust " in a locomotive, a vacuum 



vol. viii. (o.s.) — vol. 1. (n.s.) 



