484 METEOROLOttlCAL REPORT, 186!), 



AMMONIA, SALTS, &c., IN RAIN WATER. 



Ammonia, Ammonia 

 Date. parts in of 



1,000,000. Albmnen. 



Kow near Helensburg... Jan. 16, 1869 0-00 0-0 



Clydeford, Glasgow ..... . ,, ,, 1*25 O'O 



London Hospital Feb. „ 2-00 0-3 



Ditto „ „ 2-20 0-3 



Ditto „ „ 3-00 0-4 



Glasgow, St. RoUox Dec. 1868 3-75 0-0 



Ditto, Netherfield Jan. 1869 5-50 0-0 



Manchester Dec. 1868 6-00 1-0 



Newcastle-on-Tyne „ „ 5-00 & 0-6 0-0 



"Here we have it clearly put before us that the towns con- 

 tain a great deal of ammonia. This comes, it may be supposed, 

 mainly from the coal burnt, and the larger quantity in Manches- 

 ter air agrees with other results. The second column however 

 gives the ammonia from albumen, and we see that the Manches- 

 ter amount is in that respect greatest also. 



"If these results are confirmed by many cases all over the 

 country, it will be difficult to avoid drawing very distinct con- 

 clusions affecting several sanitary questions." 



The appended drawings show the different appearances when 

 a drop of the concentrated rain is allowed to evaporate on a 

 piece of glass. 



" The crystals appear different in all places tried. When the 

 air around works is examined it is necessary to keep such infor- 

 mation as this in mind. The question regarding the effect of 

 such substances on health is one which cannot receive a very 

 ready answer." 



"A specimen is under examination from North Uist. The 

 crystals are large cubes of common salt only. At Row they are 

 clearly common salt, but the crystals less complete. Before 

 great towns are reached the land changes the rain." 



"It seems certain that chlorides come directly from the sea, 

 or, in other words, that salt is continually floating in the air, so 

 that we must not be too certain that chemical works are doing 



