Meteorological Observations. 239 



did not acquire colour when exposed to a bright light, hence the 

 author concluded that mercury was present. To settle this point, 

 the author boiled the chloride of silver with a plate of gold, a little 

 tin, and muriatic acid ; the gold plate was amalgamated. He then 

 treated 150 grms. of the silver separated by the graver by M. Le vol's 

 process, seeking for the mercury in the liquid deprived of silver and 

 containing the double acetate of ammonia and mercury. By means 

 of protochloride of tin he obtained of metallic mercury 0-0035 = 0'038 

 kilogrms., the silver being 10'906 kilogrms. Thus this copper 

 contains, — 



Kilogrms. Per 1000. 



Copper 138-560 0*69280 



Silver 10-906 0*05453 



Mercury 0-038 0*00019 



Gangue 50*496 0*25248 



200*000 

 — Comptes Rendus, July 21, 1856, p. 166. 



METEOROLOGICAL OBSERVATIONS FOR JULY 1856. 



Chiswick. — July 1. Cloudless, with very dry air. 2. Dry haze : very fine. 

 3. Clear and very fine. 4. Fine : overcast : slight rain. 5. Fine: overcast : very 

 fine. 6. Very fine : lightning, with rain at night. 7. Densely clouded : rain. 

 8. Very heavy rain, cold and boisterous. 9. Fine. 10. Very fine. 11. Cloudy: 

 sUght drizzle : fine. 12. Overcast. 13. Very fine : overcast : cloudy. 14. Very 

 fine: overcast. 15. Cloudy and fine : lightning, with rain at night. 16. Rain: 

 heavy clouds and showers : very fine. 17. Very fine. 18. Overcast : drizzly : very 

 fine.' 19. Fine: overcast. 20. Slight drizzle: overcast: rain. 21. Very fine. 

 22. Sultry. 23. Slight fog : very hot : cloudy : Ughtning. 24. Shower : very hot. 

 25,26. Exceedingly fine. 27. Overcast: rain. 28. Cloudy: very fine : hazy. 

 29. Shght fog : very fine. 30. Uniform haze : very fine. 31. Slight fog : very 

 sultry : clear and fine. 



Mean temperature of the month 61'*-20 



Mean temperature of July 1855 62-99 



Mean temperature of July for th e last thirty years 63*11 



Average amount of rain in July 2558 inches. 



Boston.— inly 1 — 4. Fine. 5. Cloudy. 6. Cloudy : rain p.m. 7. Cloudy : rain 

 A.M. and P.M. 8. Fine: rain a.m. and p.m. 9. Fine : rain p.m. 10. Fine. 11. 

 Cloudy. 12. Cloudy : rain a.m. and p.m. 13. Cloudy. 14. Fine. 15. Cloudy. 

 16. Cloudy: rain a.m. and p.m. 17. Fine. 18. Rain a.m. and p.m. 19. Fine. 

 20. Cloudy. 21, 22. Fine. 23, 24. Cloudy. 25. Fine : rain p.m. 26. Cloudy. 

 27. Cloudy : rain a.m. 28—31. Fine. 



Sandwich Manse, Orkney, — July 1. Bright a.m. : clear p.m. 2. Clear a.m. 

 and p.m. 3. Clear a.m. : showers p.m. 4. Drizzle a.m. and p.m. 5. Cloudy a.m. : 

 drizzle, showers p.m. 6. Showers a.m. : drizzle, showers p.m. 7. Rain a.m. : 

 bright P.M. 8. Drizzle, showers a.m. and p.m. 9. Drizzle, showers a.m.: 

 cloudy P.M. 10. Cloudy a.m. and p.m. 11. Cloudy a.m. : rain p.m. 12. Bright 

 A.M. : bright, fine, thunder p.m. 13. Bright a.m. : cloudy, fine p.m. 14. Clear, 

 fine A.M.: cloudy, rain p.m. 15. Cloudy a.m. and p.m. 16. Drizzle a.m.: 

 rain p.m. 17. Clear a.m. and p.m. 18. Rain a.m. : showers p.m. 19, 20. Drizzle 

 a.m. : damp p.m. 21. Bright, fine a.m. and p.m. 22. Clear, fine a.m. : cloudy, 

 fine P.M. 23. Rain a.m. : cloudy, fine p.m. 24, 25. Bright a.m. : bright, fine p.m. 

 26. Clear a.m. : showers p.m. 27. Bright a.m. : showers p.m. 28. Showers a.m. : 

 cloudy, fine p.m. 29. Clear, fine a.m. : rain p.m. 30. Bright a.m. : hazy p.m. 

 31. Cloudy, fine a.m. : rain p.m. 



Mean temperature of July for previous twenty-nine years ... 55°-22 



Mean temperature of this month 54*77 



Mean temperature of July 1855 59*19 



Average quantity of rain in July for previous sixteen years ... 2*45 inches. 



