172 
REPORT— 1854. 
In Table IV. are given,— 
The amounts of ammonia per million, in the rain which fell at Paris 
during several consecutive months of 1851, as determined by M. Barra); 
1 he proportions determined by M. Boussirigault in the open country in 
Alsace, during several months of 1852; 
1 he proportions in the rain which fell at Rotliamstcd during several months 
of 185:1, in several rases determined both by Methods 1 and 2; also in that 
of several months of 1854 determined by Method 3. 
And in the second division of the Table,— 
I he actual amounts of ammonia in lbs., contained in the rain which fell 
over the area ot anlmperial acre, in the case of each of the months experi¬ 
mented upon by M. Harral at Paris, and by ourselves at Rotbamsted. 
Comparing together the determinations of the ammonia per million of the 
rains collected at Kotliamsled in April, May, June, July, ami August 1853, 
made by both the Methods 1 and 2—in the one ease dealing with hundred* of 
lbs. ot rain-water, and in the other with only 30 or 00 ounces of it—the coin¬ 
cidences arc »udl as to lead to the conclusion, that such discrepancies as there 
are, are due to manipulative ditlicultics and irregularities, rather than to 
erroneous principles inherent in the methods themselves. In the determina- 
lions for Muy and June, those made by Method 2 are indeed notubly below 
those made by Method 1. Hut the obvious deviation from the regularity in 
the proportion of the ammonia found in tlm different fractional portion# of 
t ie distillate, as scon in the detail of the determinations given in Table II., 
compared with that supposed by M. Boussingault to be so uniform, would 
! « rcatl T owtodeuee in the estimations made by Method 1. Confidence 
!" tlu ‘ ^' ner . al I’nnciple* of the various methods is, however, again afforded 
if ™ m P ar, *°n ‘he determination made in the rain of April by Method 3, 
Til .1 "T® m ll !*\ san,r: water by Method 2 as given at the foot of the 
”... ; t '®, fonner 6 ,vl,, g 0 - 967 , and the latter 0*980 parts of ammonia per 
million of the water. 1 
1 rusting, then, u* we may do, in the general approximative truth of the 
result* obtained, we find, that taking all the determinations in the monthly 
min collected at, Rot ha mated given in this Table, and which apply to that of 
oi neen separate but consecutive month*, the average amount of ammonia 
LlrTu- 7* C y ™ /W,rt iH a mim ° n °f ** The average of Boas- 
• ^ n,,lal,0t ' i m lhc °l )en country of Alsace, am! extending over 
u LTv n , 18;V2 ’ fro,n May to October inclusive, is seen to be as 
ti^of\F°n“ bl V ,h ’? f the •mount found at Rotbamsted. The esti.ua- 
2?" *' ‘ r ' lhe o^er hand, in the rain collected at Paris during 
? ° f 185, * rrora August to December inclusive, gi™ 
an .i rerege of nearly 3-$ parts of ammonia in a million of rain-water; and, 
* experiments, M. Iloussingnult has found the ammonia in the 
rain at Pans to be a* great as that observed bv M. Barrel. There can be 
no doubt, therefore o| the influence of a large city teeming with animal lift, 
Unn of rl combustion 0 | various kinds is so enormous, upon the propor* 
Sf it whiM^Ti “ 1,,ea ® bienk atmosphere, and consequently on the amount 
of it which will be washed down in the rain. 
ainoVnt Of" nT er ’ •°T Cr ’ Iocn,it y> •tricily so speaking, influences the actual 
‘ nLa I™ 1 " surfacc emanations or otherwise, in otherwise 
of ir in a^vpn 0 »' l,ry ’ " *, lil1 a < l MeBtion ^ut in reference to the proportion 
tho vll-iafb.nrvvi j' 1 '!• rU ‘? , . it is at a,, y ri,te interesting to observe, that 
i; rent but entire m Tk ° U u^ In tbe a,nou, ‘t of the ammonia in rain of di^ 
rnnrmnfc of considered '» connexion with the registered 
amounts of the fall, the direction of the wind, and the general characters of 
