86 • REPORT — 1859. 



Its supposed value is about £8640: thus 2217 ozs. — 57 loss (about) = 2160x4 

 (value of gold per oz.) = £8640. 



Unless the Government, or some person taking a great interest in these matters, 

 would secure it, I should like to see it in one of our national museums, being the pro- 

 duce of one of our most important colonies. 



Note. — This nugget was melted September 22, 1859, and yielded gold to the 

 amount of £8376 10s. lOrf. 



On the Comparative Value of certain Salts for rendering Fibrous Substances 

 Non-inflammable. By F. Versmann, F.C.S., and A. Oppenheim, Ph.D. 



As nitrogen forms a constituent element of the animal fibre, carbonate of ammonia is 

 among its gaseous products of decomposition, and prevents the animal fibre from burn- 

 ing with a flame and from communicating ignition. The vegetable fibre, however, if 

 decomposed by heat, evolves gaseous hydrocarbons and oxide of carbon mixed with only 

 little carbonic acid, and the danger arising herefrom is the principal reason why paper is 

 frequently replaced byparchment, and wood by stone, iron,&c. But as the use of cotton 

 and of linen increases by necessity from year to year, it is desirable that means should be 

 employed for preventing the danger of conflagrations arising from these highly inflam- 

 .mable substances. Glue and albumen, if introduced into the vegetable fibre, besides 

 injuring the appearance of the same, prove to be useless for the subject in view. They 

 contain only as much nitrogen as the animal substances from which glue is made, viz. 

 about 18 percent. Urea, however, containingalarge proportion of nitrogen, is efficacious, 

 if an amount of 28 per cent, is introduced into a piece of muslin, which consequently 

 contains only 10*2 percent, of nitrogen in the shape of an animal substance. But for all 

 practical purposes we must look for an expedient among the number of inorganic salts, 

 and this has been done for a considerable time. In 1735 already a patent for preventing 

 substances from flaming was granted to one Obadiah Wild, who applied a mixture of 

 alum, borax, and vitriol, principally for making non-inflammable paper for cartridges. 

 A complete list of the literature on anti-flammable expedients will be given in another 

 place. It must be mentioned, however, in this abridgement, that Gay-Lussac is the 

 only chemist who compared (in 1821) the action of a small number of salts, by deter- 

 mining which of them are sufficient, if taken up by linen to the amount of 10 per cent., 

 and, finding no salt to answer in this proportion, by further determining which are 

 sufficient, if taken up to the amount. of 20 per cent. 



The annexed Table, comparing a considerable number of salts, including all those 

 which seemed to be of practical interest, and some others on account of chemical ana- 

 logies, has been composed by employing another method; viz. by determining the 

 smallest proportions of different salts required in solution, if this solution shall have 

 the desired effect. This method brings out some remarkable facts, and allows of the 

 following general conclusions : — 



Every inorganic salt, if applied in solution to fabrics, diminishes their inflammabi- 

 lity by absorbing heat and excluding the free access of the air. Even those salts, 

 which, like chloride of sodium, proved not to protect the fibre, would most probably 

 do so if sufficiently concentrated solutions could be obtained. 



More active than other salts are those which are easily fusible (such as borax), or 

 partially or entirely volatile, thereby rarefying the inflammable hydrocarbons (such as 

 certain salts of ammonia and as the carbonates of soda), or those, which owing to their 

 peculiar physical constitution, firmly envelope the fibre, such as the tungstate of soda. 

 It will be seen that some salts frequently recommended have no practical value ; that 

 alum, for instance, is required in a proportion that injures the appearance of the 

 fabrics; that carbonate of ammonia is too little soluble, and, like sal-ammonia, too 

 volatile ; and that borax, owing to its boracic acid, destroys the fabric at higher than 

 ordinary temperatures. A solution of only one per cent, of borate of ammonia has 

 the same effect, and boracic acid alone cannot protect the fibre. 



The experiments referred to were not confined to the laboratory, but repeated under 

 different circumstances in Her Majesty's laundry at Richmond, and at the Finishing 

 Works of Mr, W. Crum, and of Mr. Cochran of Glasgow. It was found thereby that 

 only the following five salts and mixtures allow of a practical application : — the phos- 



