funning reddish-lirowii fumes of oxides of nit ro^vn.'' which form with 

 \\ ater a co]n| on i n 1 ci i] it am 1 1 iu' nit ro;_;e n, oxygen, and hydrogen namely, 

 nitric acid. 1 " N 1 1 < ' ... The presence of t lie lat ter is easily reco^iii.M'd, not 

 only ir.'iii it-- I'IM Menu iu' litmus paper, Itut al>o Irom its acting as a 

 l"'\verful oxidistT even <if inci'cuvv. Conditions similai 1 to these occur 

 111 nature, during a thunderstonn or in otlier eleetneal discharges 

 accomplished in the atmosphere* whence it mav lie understood that 

 air and rain-water always contain traces of nitric acid. 11 



Further observations >ho\\ed that under the inlluence of electrical 

 discharges, 1 - silent as \vell as witli sparks, nitrogen is able to enter into 



'If.: inn of one vohniH- of uitvo^'ii and hmrteen vohunes of hydni^en be burnt, 



then water and a ci 'i i -it li Tal ilf quantity of nitric acid arc formed. It may lie partly due 

 in quantity ''t' nitric acnl i- produced in ilic -low oxidation of nitro- 

 genous -uh.-taiices :n an excess (it air. '1 hi- is especially facilitated by the presence of 

 ii ii the nitric aci<l t'tinned can combine. It a iralvanic current lie passed 

 '. ter < ontainin^ the nitre-en ard oxygen of the air in solution, then the hydro- 

 _,!! and oxygen -' free combine uith the iiitni^reii. furniiiiL;- aninioiiia and nitric a -id. 



Wh.-n cop]n r is oxidised at the expense of the air at the ordinary temperature in the 

 pre-ence of ainiiionia. oxygen is ah-orbcd. not only for coinliinat imi with the coppei-. lut. 

 a Ui i fi ir the fi irmatii ai of nit ric acid. 



The coinl ination of iiitroL. f <'ii with nxy^cn, even, for example, \>y the action of electric 



-parks, i- not accompanied I >y an explosion or rapid comliinat ion. a> in i he action of > parks 



. of oxy_'en and hydrogen. 'Diis i<; explained hv the fact that heat is not 



evolved iii tin- combination of nitro-en with oxygen, lnit is a'l-orhed an exjieiiditure of 



eiieru'v is reijuiri d. there is no evolution ol eiiei'LTy. In lact. there will not he the trans- 



mi~-ion in particle to |i.-irticle which occur- in the explosion of detonating pis. 



!-'.acli -pur!: will aid the formation of a certain quantity of the compound of oxygen and 



. J.iil ill not excite the same in the nei^hltotiriiiLr particles. I n ot her \vor.U. t he 



comliinat ion of hydro-en \vit h oxyuren i- an exothermal reaction, and the ci >m hi nation , ,f 



The! ol the explosion of detoiiatin- pis if it he /// r.rrv.s'.s are especially 



: in of nitroureii. If a mixture ol t wo volumes of detoniitiiiLT -:as 



, . - air he exploded, then one-tenth ot the air is con\ erted into nitric acid. 



-, i id con , . ft er the expl.i-ion has taken place there remain^ only nine tent lis of the 



n. If a larje pri 'pori ion of air he taken for instance, four 



,\o \ ohm ie- di detonat in;_ f u f ns then it he tempera tun- of t he explosion 



i ii remains iiiicliaiiLTed. and no n it ric acid is formed. 



'I . uletohe .,b<ened in making n^eof the eudiometer na ui.-ly. t ha! to weaken 



e of the ex ] oil l|o| leS-, th.ill all eqll.il Volume (.1 air should he added to the 



, , . (i llieo-.her hand, a lar-e exceNsmust ii.it he taken, as no explosion 



: . , n ..hide, uh,, li.as ue-hall afterward- learn, in 'he pivsenceof waterand 



,, : , :v/ , ,, , ., c M d. l',\ the aci : |, m ,| char-e Hinni-li air hotli oxide- ,,f 



, lor d. Inil with a leehle ,|i char-e Hi,, formation 



I III. e-o| tro-el, are not prodllc. .1. h\ wllirll fact Merthelot 



n 'I'),, ,,'; e .e id c. uita ed 111 the nd. stream water < ha pt ,-r I . n, ,| ,. -J ,. wells. A'c.. 

 proe. ed i . Irid. ,,,-,.,., com|,oiuiils which ha\e 



fa.l!t ,: .: to ,. ,t. r. ' /. 



!-' Thi cu. i eri. cuit;, t'-r r. ad i ' n. \\ hi. h under normal condition- is 



. ; to lln d. : that under tin- influence of an electric discharge gaseous 



