524 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



become of some practical value, viz., in regard to the product 

 resulting from the action of strong alkalies upon the fibre of 

 the New Zealand flax as well as of the Manilla hemp. By 

 boiling either of these fibres for four hours in a strong solu- 

 tion of caustic potash, a pulp is obtained similar to that used 

 in paper-making, with the difference, however, that, when dry, 

 it shows considerable strength, so that an untwisted thread 

 will support a weight of several pounds. Yet, while one single 

 drop of water immediately destroys the cohesion, neither al- 

 cohol nor ether have any such effect. Mr. Skey suggests that 

 this puli^ may serve as a suitable material for an entirely 

 new class of fabrics on account of the ease of manufacture, 

 the length of fibre, the clear color, the beautiful lustre, etc. 

 The pulp is easily moulded into any desired shape, and Mr. 

 Skey thinks that, in drying, some substance could be added 

 by which the absorption of moisture will be prevented and 

 the desired durability thus obtained. 13 C,viil, 1872,546. 



MERCURIAL PHOTOGRAPHIC PRINTS. 



Professor Merget, of Lyons, submits a new process of print- 

 ing from photographs without the agency of light. He 

 spreads a few drops of mercury upon a copper plate, covers 

 it with blotting-paper, and places upon this a common posi- 

 tive photograph. The latter is slightly heated, and its col- 

 lodion side brought in contact with the paper. The mercury 

 evaporates, and, after penetrating the blotting-paper, is pre- 

 cipitated upon the picture in accordance with the shades of 

 its silver deposit. Half an hour is sufficient for this opera- 

 tion. The photograph thus prepared is pressed in a common 

 copying-press upon paper impregnated with a salt of any 

 of the noble metals, such as gold, silver, iridium, platinum, 

 etc., and its mercury immediately reduces the metallic salts 

 in the paper and gives a sufficiently good copy. The print- 

 ing, however, must be done in the dark when nitrate of silver 

 is used in the paper. 13 (7, ix., 1872, 614. 



ENAMEL FOR COOKING VESSELS. 



In order to prevent oxidation in cooking vessels of copper, 

 a German polytechnic journal recommends an enamel which 

 is said to fully resist the action of vegetable acids. It consists 

 of twelve parts of white fluor spar, twelve parts of gypsum 



