i^ecompa/ition Jtf Borax.— Culture of Barren Mountains. - 5195 



^Its, component parts, is inflammable matter, which may be converted into cpal. I obtaine>l pf 

 altue coal (mixed yvithfome ^rth, £*/>«r. XXXII. and LIV.), according to the above-de- 

 ,fcribed experiments {£xp^r. XXH- XXVI.— -XXX.), thiny grains anjl three quarters, in 

 ithe whole ; and by other experiments, often repeated, in general, one gr^in and a. half, more 

 .or lefs. Evei7 <jther .fMbftance liablctp be changed into coal (as gum, tartar, ,fug?r, &c.) 

 .fuffers ,tl}is change l\y a gentle jieat, and deflagrates with nitre, in the degree of heat nc- 

 .ceflary to melt the former. But fcdative fait can, bear a red heal for many hours, without 

 ;(hewing any figns of becoming coal, of burning, or of deflagration. Aftoniftiing pheno- 

 .menon ! What menftruum prefervesit fo fecurely againft the alTauJt of force, in a diflblvcd 

 .ftate, and yet fufFers itfelf to be fspyirated from it, by more gentle means ? What power exifte 

 .here, to protc(5l the inflammable particles (which afterwards turn to coal J fo efFedualljr 

 ,.againft a degree pf heat yvhich nothing elfe can refill? Of what nature is .the /alt obuinefl 

 ,in conjuntSlion with the coal ? Thefe are all qu^ftipns which excite great, intereft, ^ut which 

 .are not eafily anfwered. How far I have been fuccefsful in refolving them, fome fubfequent 

 e/Tayswill i)jq,w ; wljich 1 fhall have the honour to lay before the Royal Society, as foon asl 

 .fhallhavc fufficiently repeated the experiments I have already made. 



JV. 



'Ohfervat'ions on the Means by which the Mountains in the Ceyennes are rendered fertile. 



By CiT. ChaPTAL. 

 ■J 



:±NDUSTRY isthe chifd of want: this axiom, of which thr truth is eftabliflied on the 



experience of every age and climate, direfts our fearch after prodigies of agriculture to 

 tbofe places only which appear to be abfolutely deprived of natural advantages. In no 

 place has this truth received a more ftriking -degree of confirmation than in the dry and 

 i barren chain of mountains called the Cevennes. They are almoft entirely formed of fteeip 

 roclcs ; "but the power of man has fucceffively converted them into fertile lands ; and this 

 Ibil, which in paft ages would not have afforded fubfiftence for one family bf-favages, does, 

 at this moment, fupport two or three hundred thoufand inhabitants. .In this tltftri£t, every 

 thing is the produfl: of art ; and here it is that we m.^y, with the greateft efFeft, ftudy the 

 creative powers ,cf human induftry. I fliall here relate the means by which th«fe -changes 

 i have been made. ' 



I {hall confine myfelf. at prefent-to the defcription of two procefles, which are ftill daily 



praftifed, and which may hereafter be adop'ed with advantage in many parts of France. 



It is a well-known fa<3: that the waters which flow down the fides of a mountain carry 



J the-earth .along with, them^-and wear furrows or ravins of a greater or lefs depth, according 



,•^0 the hardnefs of the rock, and fteepnefs of the defcent. Thefe two effefts are conftant and 



^inevitable. By a fcries of thefe progreflive degradations, the hardeft rock is laid baiej deep 



