212 THE POPULAR SCIENCE MONTHLY. 



directions, best illustrated by the extraordinary development of the 

 cbemical methods for manufacturing wood-pulp. By the im- 

 proved processes, strong fibers suitable for fine felting on the 

 screen and fit for the best grades of certain lines of paper are 

 given to us from rather inferior sorts of wood. He would be a 

 rash prophet who should venture to predict what will be the 

 future of this wonderful industry, but it is plain that the time is 

 not far distant when acres now worthless may be covered by trees 

 under cultivation growing for the pulp-maker. 



There is no department of economic botany more promising 

 in immediate results than that of arboriculture. 



V. Vegetable Fibers. — The vegetable fibers known to com- 

 merce are either plant-hairs, of which we take cotton as the type, 

 or filaments of bast-tissue, represented by flax. No new plant- 

 hairs have been suggested which can compete in any way for 

 spinning with those yielded by the species of Gossijpium, or cot- 

 ton, but experiments more or less systematic and thorough are 

 being carried on with regard to the improvement of the varieties 

 of the species. Plant-hairs for the stuffing of cushions and pillows 

 need not be referred to in connection with this subject. 



Countless sorts of plants have been suggested as sources of 

 good bast-fibers for spinning and for cordage, and many of these 

 make capital substitutes for those already in the factories. But 

 the questions of cheapness of production, and of subsequent prep- 

 aration for use, have thus far militated against success. There 

 may be much difference between the profits promised by a labora- 

 tory experiment and those resulting from the same process con- 

 ducted on a commercial scale. The existence of such differences 

 has been the rock on which many enterprises seeking to intro- 

 duce new fibers have been wrecked. 



In dismissing this portion of our subject it may be said that 

 a process for separating fine fibers from undesirable structural 

 elements, and from resin-like substances which accompany them, 

 is a great desideratum. If this were supplied, many new species 

 would assume great prominence at once. 



VI. Tanning Materials. — What new tanning materials can 

 be confidently sought for ? In his Useful Native Plants of 

 Australia, Mr. Maiden * describes over thirty species of " wattles " 

 or Acacias, and about half as many Eucalypts, which have been 

 examined for the amount of tanning material contained in the bark. 

 In all, eighty-seven Australian species have been under examina- 

 tion. Besides this, much has been done looking in the same direc- 

 tion at the suggestion and under the direction of Baron von 

 Mueller, of Victoria. This serves to indicate how great is the 



* Useful Native Plants of Australia. By C. H. Maiden, Sydney. 



