Meteorological Observations. 151 



stalline compound, which is no doubt a hydrate of sulphuretted 

 hydrogen, must be produced when a small quantity of water is en- 

 closed with hydrate free from acid ; the water then combines with 

 the sulphuretted hydrogen under the pressure of the condensing 

 sulphuretted hydrogen (17 atmospheres). Under this pressure it is 

 permanent at ordinary temperatures. If the tube be heated in water 

 to 86° F., the compound dissolves, and rapidly becomes fluid, 

 returning to a solid state again on being cooled to the ordinary 

 temperature. — Anii. der Chem. und Pharm., Ixxxv. p. 374. 



METEOROLOGICAL OBSERVATIONS FOR DEC. 1853. 



Chiswick. — December 1. Overcast: fine: clear and frosty. 2 — 4. Dense fog. 

 5. Foggy: slight rain. 6, 7. Foggy: overcast. 8. Foggy: fine. 9. Fine: slight 

 rain. 10,11. Cloudy. 12. Hazy: uniformly overcast. 13. Foggy. 14. Over- 

 cast. 15. Snovring : clear and frosty. 16. Overcast: clear, with bright sun: 

 severe frost at night. 17. Severe frost : overcast : frosty. 18. Clear : overcast. 

 19. Uniformly overcast : clear and fine : cloudy. 20. Hazy-, 21. Densely clouded : 

 boisterous at night. 22. Overcast. 23. Cloudy : clear. 24. Clondy : clear and 

 frosty. 25. Frosty : hazy : clear, with sharp frost at night. 26. Frosty : fine : 

 frosty. 27. Clear and frosty : hazy : clear and frosty. 28. Clear and frosty : fine : 

 severe frost at night. 29. Severe frost : clear and fine : frosty. 30. Snow- 

 shower : frosty. 31. Very clear and frosty: partially overcast: sharp frost at 

 night. 



Mean temperature of the month i 32°'49 



Mean temperature of Dec. 1852 46 "SB 



Mean temperature of Dec. for the last twenty-eight years . 39 "64 

 Average amount of rain in Dec 1-5 inch. 



Boston. — Dec. 1. Cloudy : rain a.m. 2. Fine. 3. Cloudy. 4, 5. Foggy. 6. 

 Cloudy: rain A.M. 7. Foggy. 8. Fine. 9. Fine: rain p.m. 10. Fine: rain 

 early a.m. Ml — 13. Cloudy. 14. Fine. 15. Snow and rain a.m. and p.m. 

 16. Cloudy: snow a.m. 17. Cloudy. 18,19. Fine. 20, Cloudy: rain p.m. 

 21. Cloudy: rain a.m. and P.M. 22,23. Cloudy: rain a.m. 24. Cloudy. 25. 

 Foggy. 26. Foggy : rain and snow p.m. 27. Fine : snow p»m. 28. Snow a.m. 

 and P.M. 29. Fine. 30. Fine; snow a.m. 31. Fine. 



Sandwick Manse, Orkney.— Dec. 1. Hazy a.m. : rain p.m. 2. Damp a.m. : 

 drops p.m. 3. Bright a.m. : cloudy, aurora p.m. 4. Clear a.m. and p.m. 5. 

 Bright A.M. : clear, aurora p.m. 6. Clear a.m. : clear, aurora S. p.m. 7. Bright 

 A.M. : frost, showers p.m. 8. Showers a.m. and p.m. 9. Showers a.m. : clear p.m. 

 10. Bright a.m.: fine p.m. 11. Frost a.m.: dauip p.m. 12. Damp a.m.: 

 showers p.m. 13. Bright a.m. : clear, a.m. lunar halo p.m. 14. Damp 

 and P.M. 15. Cloudy a.m. : clear p.m. 16. Damp a.m. : clear p.m. 17. Clear, 

 frost a.m. and P.M. 18. Bright, frost a.m. : clear, frost p.m. 19. Showers a.m. : 

 clear p.m. 20. Showers a.m. : clear, frost p.m. 21. Clear, frost a.m. : clear, 

 frost, aurora p.m. 22. Cloudy, frost a.m. : showers p.m. 23. Showers a.m. : 

 hhowere, aurora p.m. 24. Cloudy a.m. and p.m. 25. Cloudy a.m. : sleet-showers 

 P.M. 26. Hail-showers A.M.: snow-showers p.m. 27. Snow drift a.m. and p.m. 

 28. Snow-showers A.M. : snow, cloudy p.m. 29. Thaw: showers a.m. and p.m. 

 30, 31. Snow-drift a.m. : snovv-sbowers p.m. 



Mean temperature of Dec. for twenty-six previous years ... 41'''18 



Mean temperature of this month 38 -97 



Mean temperature of Dec. 1852 40 -74 



Average cpiantity of rain in Dec. for thirteen previous years 413 inches. 



