MUSTA PAAT 381 



as an established fact that the sulphate of ammonia may be most advantageously 

 applied in the finishing of muslins and similar highly inflammable fabrics. 



The authors felt, however, the necessity of inquiring further into the effect which 

 ironing would have upon fabrics thus prepared ; for all the above-mentioned salts, 

 being soluble in water, require to be renewed after the prepared fabrics have been 

 washed. 



Now, the sulphate of ammonia does not interfere with the ironing so much as other 

 salts do, because a comparatively small portion is required : but still, the difficulty is 

 unpleasant, and sometimes a prepared piece, after being ironed, showed brown spots 

 like iron-moulds. On covering the iron with plates of zinc or brass, these spots did 

 not appear ; but the difficulty still existed, and a white precipitate covering the plate 

 showed evidently that it is the volatile nature of the salt which interferes with the 

 process. An attempt to counteract this action of the salt, by adding wax and similar 

 substances to the starch, remained also without any result. 



For all laundry purposes the tungstate of soda only can be recommended. This 

 salt offers only one difficulty, viz., the formation of a bitungstate, of little solubility, 

 which crystallises from the solution. To obtain a constant solution this inconvenience 

 must be surmounted ; and it was found that not only phosphoric acid, in very small 

 proportion, keeps the solution in its original state, but that a small percentage of 

 phosphate of soda has the same effect. 



The best way of preparing a solution of minimum strength is as follows : A con- 

 centrated neutral solution of tungstate of soda is diluted with water to 28 Twaddle, 

 and then mixed with 3 per cent, of phosphate of soda. This solution -was found to 

 keep, and to answer well ; it has been introduced into Her Majesty's laundry, where 

 it is constantly being used. 



The effects of the soluble salts having been thus compared, a few remarks are neces- 

 sary respecting the means which may be adopted permanently to fix anti-flammable 

 expedients, so that the substances prepared may be wetted without losing the property 

 of being non-inflammable. 



Relying upon the property of alumina as a mordant, we tried the combination of 

 os.ide of zinc and alumina, obtained by mixing solutions of oxide of zinc in ammonia 

 and of alumina in caustic soda ; but, although this precipitate protects the fibre, it 

 does not adhere to it when washed. 



The oxychloride of antimony, obtained by precipitation from an acid solution of 

 chloride of antimony by water mixed only with a little ammonia, is a good anti-flam- 

 mable, and it withstands the action of water, but not that of soap and soda. It was 

 not found that the solution of this and other salts in muriatic acid injured the texture 

 of the fabric as long as this was dried at an ordinary temperature. 



The borate and phosphate of protoxide of tin act effectually, if precipitated in the 

 fibre from concentrated solutions of these salts in muriatic acid by ammonia ; they 

 withstand the influence of washing, and give a yellow tinge to the fabrics. 



The same remarks apply to arsenate of tin. The stannates of lime and zinc pro- 

 tect the fabric, but do not withstand the action of soap or soda. 



The oxides of tin give a favourable result, inasmuch as they really can be per- 

 manently fixed ; the yellow tinge, however, which they impart to the fabrics will 

 always confine their application to coarse substances, such as canvas, sail-cloth, or ropes. 



The canvas thus prepared must be dried and then washed, to remove the excess of 

 precipitate. Salt-water does not remove the tin from the canvas. 



A piece about 40 yards in length has been prepared by order of the Storekeeper- 

 General of the Royal Navy ; but it was found to have lost in strength, and increased 

 in weight too much to allow of its application. 



These experiments, however, being the first successful attempts permanently to fix 

 some anti-flammable agents, may have some interest, although they leave but little 

 hope that the result of fixing anti-flammable expedients will ever be obtained without 

 injuring the fabrics. 



By determining the comparative value, and ascertaining the difficulties which have 

 prevented, till now, the general use of protecting agents, the authors were led to 

 exclude a number of salts hitherto proposed, and to advocate the adoption of sul- 

 phate of ammonia, and of tuugstate of soda, in manufactories of light fabrics, and 

 in laundries. 



They hope, therefore, that the general introduction of these salts will soon greatly 

 reduce danger and loss of life through fire. 



2VIUESHlj.Bja.Kri>. Thin shelly bands occurring in the coal-measures are called 

 by the miners mussel-band, or mussel-bind. 



IVItfST is the sweet jxiico of the grape. 



MXTSTA PAAT. Hibiscus cannabinus. A vegetable fibre, much used in Asia. 

 See FiBitKs. 



