5/0 



CHAPTER Vr. 



UTILIZATION OF STOxN'E, GRAVEL, ETC. 



In mountuiu-fin-ests, the utilization of stone is frequently an 

 im portent item of forest revenue ; quarrvinfif the better kinds of 

 stone increases in importance with the expansion of towns, the 

 more substantial nature of the buildings erected and the con- 

 stantly extending means of communication. Independently of 

 the fact, that an absolutely necessary want is thus met, the forest 

 owner's own pecuniary interest will prevent him from opposing 

 ii well-regulated system of quarrying, for the best production of 

 wood will never pay so well as leasing quarries. 



1. Ditf'rrcnt kinds of Stoiir. 



The following kinds of stone are utilized : — Hewn-stone which 

 is regularly shaped, and for which the fine, compact sandstones 

 of the Cambrian, Silurian, New Red Sandstone and Tertiary 

 formations, also trachyte among eruptive rocks, &c., are most in 

 demand. [In Hritain also Bath oolite, Aberdeen granite, &:c. 



-Tr.] 



Broken stone used in rubble-masonry, for foundations, S:c., 

 for which almost any kind of stone is suitable ; — or paving 

 stones, for which the hardest material, basalt, phonolith, diorite, 

 fine-grained syenite, iSrc, are most suitable. Slate for roofing 

 from the Cambrian and Silurian formations, and lignite nt ar 

 Liegnitz and Frankfort are also valuable. The forester should 

 everywhere favour quarrying, not only on financial grounds, but 

 also for national-economic reasons. Calcareous rocks are also of 

 great importance, serving as building-stone or for lime-burning, 

 for which purpose they are the more valuable the less clay they 

 contain. Quarries of gypsum, felspar and kaolin are rare. The 

 list may be closed by enumerating sand, gravel, marl and clay, 

 which are almost fv.iv wlicic more or less in demand. 



