THE TECHNOLOGIST. [Joke 1, 1865. 



512 MINERAL SUBSTANCES FOR WRITING ON. 



and such like, as also in the rudiments of drawing. Thus the slate is 

 eminently adapted for all exercises, as it allows of a continued use and 

 saves quantities of paper. Our school-teachers would undoubtedly find 

 it a hard matter to get on nowadays without this so useful article, and yet 

 it is not so very long ago that writing-slates were altogether unknown in 

 our schools. It is scarcely a hundred years old, being the most recent 

 of all the writing materials at present in use among us, while the raw 

 material itself, the slate-rock, was used in the very earliest ages, and 

 that they, in spite of their hardness and rigidity as compared with the 

 pliant white smooth paper, should have met with acceptance and rapid 

 diffusion, is a proof of their manifold advantages. It may be con- 

 fidently asserted that they first came into use in the latter half of the last 

 century ; their use was rapidly extended, and by thi* time they are to 

 be found well-nigh all over the world. 



But the very look of the slate tells us that it is still in its infancy. 

 Its manufacture is almost the same as it was at first, nor has any 

 machinery as yet dared to supplant the hand-labour or to produce a better 

 and more suitable article instead of the old clumsy one, and that in any 

 quantity. For a whole century scarcely any improvement or perfection ! 



Slates are manufactured in the manner above mentioned both in 

 Germany, England, and France, all being much about the same with 

 respect to quality. The writing-slate in use in the present clay, though 

 certainly no longer the clumsy unsightly thing it once was, is yet 

 capable of vast improvement. It is so often wanting in the proper 

 smoothness, or the colour is too light and greyish, so that writing does 

 not stand out sufficiently plain. Then, again, the slate may be too 

 hard, precluding the light use of the pencil ; while the frame, being 

 made of common deal, soon gets dirty, and nowhere is a tasty elegant 

 article pleasant to the eye to be met with. On account of their brittle- 

 ness, it has often been attempted to supersede them by slates made of 

 tin, wood, or paste-board, which, though possessing the advantage of light- 

 ness, on the other hand are attended by so many disadvantages, such as 

 warping, destruction of their enamel coating, which either chips, cracks, 

 or gets washed off, and is always sooner or later entirely worn off, as to 

 render it impossible for them to supplant the true slate. 



If the manufacture of slates has been hitherto in its infancy, our 

 age demands an attempt at perfecting them, and thus to develope this 

 branch of industry by means of the assistance our times afford. Slate 

 and black-lead are first cousins ; the same age has called them both 

 into existence. Black-lead has become an indispensable writing material 

 for our age, and the manufactory of A. W. Faber at Stein, near Niirn- 

 berg, produces an article in this branch which is acknowledged 

 throughout the whole civilised world to be a most excellent one, and 

 now the same manufacturer intends to attempt to raise the more 

 humble brothers ot black-lead, slate, and slate-pencil to a more honour- 

 able position. 



