\^4! AEROSTATIC MACHINHS. 



it Is now known, always contains this alcali, but as the quan- 

 tity of foda contained in this foffil, is twice as large as that 

 which exifts in the fonorous porphyry, I have not 1-^efitated at 

 giving it the name of natrolite. 



VI. 



On the Employment of JeroJ^atic Machines in the Military Science ^ 

 and for the Conftriidion of Geographical Plans.* By Citizen 



A. F. LoMET.f 



Prefent ftateof ^ HE acroftatic art is ftill in its infancy; and whatever pro- 

 aeroftation. grefs may have been already made in it, it is impoffible to 

 forefee all the refources it may afford, or to determine the li- 

 mits of its utility. Time and experience rauft fix our opinions 

 refpeding it; but it is of confequence to obtain the affiftance 

 Its Improvement of learned men and artifts in this interefting purfuit; and as the 

 fhouH be pro- fmallefl: inveftigations of this nature are generally too expen- 



tnoted by go- . ° o y r 



vcrnment. five for individuals, it is necefTary that the government ftiould 



fupport an eftabliftiment particularly devoted to t!ie praftice 



and improvement of the procetTes which conftitute it. 



Advantages to Aeroftats will turnifli, in prefence of an enemy, one or 



be derived from more points of obfervation at pleafure, from which the pofi- 



i£s ufe in war. . , . , • . , • n i- i 



tions he occupies may be le^onnoitred, bis movements Itudied, 



and, his manoeuvres judged of in the grofs, or appreciated in 

 the moft minute detail. It may be prefumed that thefe ma- 

 chines will become of the moil indifpenfable utility in war, be- 

 caufe they fupply it with an extraordinary means, hitherto un- 

 known, of making obfervations, which may in an inftant de- 

 termine the fate of battles, fecure the difpofi tions for a vigorous 

 defence, or at leaft point out the moment and the moft con- 

 venient outlets for a reireat; and more particularly to draw at- 

 tention to the advantages which an army may derive from bal- 

 laftancc. loons, it will be fufficient to remember the happy ufe made of 



them at the battle of Fleurus, 



* Adjutant-commandant, formerly keeper of the colleftion of 

 models belonging to the Polytechnic School, and now at the head of 

 the fixth uivifion of the war department. (Military operations and 

 movement of the troops.) 



t From Journal de TEcole Polytechjiique, Tome IV. p. 252. 



The, 



