To convey some idea of the number of substances which have been really tried; in the Library of the British Museum may be seen a book, printed in low Dutch, containing upwards of sixty specimens of paper, made of different materials, the result of one man’s experiments _alone_, so far back as the year 1772. In fact, almost every species of tough fibrous vegetable, and even animal substance, has at one time or another been employed: even the roots of trees, their bark, the bine of hops, the tendrils of the vine, the stalks of the nettle, the common thistle, the stem of the hollyhock, the sugar cane, cabbage stalks, wood shavings, saw dust, hay, straw, willow, and the like. At the present time straw is occasionally used, sometimes in connection with other materials, such as linen or cotton rags, and even with considerable advantage, providing the processes of preparation are thoroughly understood. Where such is not the case, and the silica contained in the straw has not been destroyed (by means of a strong alkali), the paper will invariably be found more or less brittle; in some cases so much so as to be hardly applicable to any purpose whatever of practical utility. Specimens, numbered 18 and 19, affixed at the end of this work, are manufactured from as much as 80 per cent. _straw_ and 20 per cent. _rope_, and certainly, as regards toughness, are excellent. No. 20, is manufactured almost entirely from _wheat straw_, which is first bleached to the utmost, and then blued by an admixture of ultramarine. The waste, however, which the straw undergoes, in addition to a most expensive process of preparation, necessarily precludes its adoption to any great extent. An ingenious invention has recently been patented for converting large blocks of wood into paper pulp; but to what extent it is likely to receive favourable attention at the hands of paper makers generally, is quite impossible to say. The invention is very simple, consisting merely of a wooden box enclosing a grindstone, which has a roughened surface, and against which the blocks of wood are kept in close contact by a lever, a small stream of water being allowed to flow upon the stone as it turns, in order to free it of the pulp, and to assist in carrying it off through an outlet at the bottom. Of course, it is not expected, that the pulp thus produced should be employed for any but the coarser kinds of paper, in the manufacture of which there has hitherto been found the greatest scarcity of material. For all writing and printing purposes, which manifestly are the most important, nothing has yet been discovered, to lessen the value of rags, neither is it at all probable that there will be; indeed, the value of paper for some time past has considerably declined, while during the most exciting period of last year, the scarcity so much talked of, was, in fact, comparatively trifling.