Meteorological Observations. 79 



this mineral occurs in schistose talc, and consequently in a silicate. 

 A series of experiments proved that silica is entirely wanting in na- 

 tive aluminates, such as the corundum of China and Bengal, Oriental 

 sapphire, the spinel of Ceylon and Norway, the gahnite of Ekeberg ; 

 and that the silica found by other chemists comes from the agate 

 mortar in which the mineral is pulverized. 



Though the bisulphate of potash is very advantageously employed 

 in the analysis of aluminates, it is not applicable to that of those si- 

 licates which are not decomposable by acids. Felspar is only par- 

 tially decomposable by this salt : it is therefore evident that silica is 

 a much stronger acid than alumina when it acts the part of an acid ; 

 for if the bisulphate of potash so readily effects the decomposition of 

 aluminates, it is entirely because alumina always acts as a base with 

 sulphuric acid. — Ann. der Chem.und Pharm., and Journ. dePharm. et 

 de Chim., Mai 1842. 



SOCIETE GEOLOGIQUE DE FRANCE. 



We are able to inform our readers, that the great Annual Meeting 

 of the French Geologists will take place this year on Sept. 4th, at 

 Aix (dept. Bouches du Rh6ne), and we have no doubt will be at- 

 tended by a vast number of foreigners, attracted both by the beauty 

 and geological interest of the neighbourhood. 



METEOROLOGICAL OBSERVATIONS FOR MAY 1842. 



Chiswick. — May 1,2. Clear and very dry. 3,4. Very fine. 5. Cloudy: heavy 

 rain. 6. Fine: showery. 7. Rain: stormy showers. 8. Cloudy: stormy. 

 10, 11. Very fine. 12. Drizzly. 13 — 15. Slight haze in the mornings: very 

 fine : clear at night. 16, 17. Very fine: clear. 18, 19. Overcast. 20. Densely 

 clouded. 21. Cloudy and fine. 22. Cloudy and fine: slight rain. 23. Cloudy. 

 24. Rain. 25. Rain : overcast. 26. Rain : cloudy : clear at night. 27. Cloudy 

 and fine. 28. Very fine. 29,30. Clear and very fine. 31. Very fine : cloudy. 



Boston. — May 1, 2. Fine. 3. Cloudy. 4. Fine. 5,6. Fine : rain p.m. 7. 

 Cloudy: rain a.m. and p.m. 8. Windy. 9 — 11. Fine. 12. Rain. 13. Fine. 

 14. Foggy. 15, 16. Fine. 17— -19. Cloudy. 20. Rain. 21, 22. Cloudy. 



23. Fine. 24. Rain : rainy day. 25. Cloudy. 26. Rain : rain early a.m. 

 27. Cloudy. 28. Fine: rain early a.m. 29. Fine. 30. Cloudy. 31. Fine. 



Sandwick Manse, Orkney. — May 1 . Clear : fog. 2. Cloudy : clear. 3. Clear : 

 cloudy. 4. Cloudy : damp. 5. Cloudy: rain. 6. Bright: cloudy. 7. Cloudy : 

 thunder. 8. Showery. 9. Cloudy. 10. Rain: clear. 11, 12. Cloudy. IS- 

 IS. Clear. 16. Clear: fog. 17. Fog cloudy. 18. Cloudy. 19. Cloudy: 

 drizzle. 20. Cloudy: shower. 21. Bright: shower. 22. Clear. 23. Clear: 

 fog. 24. Clear: cloudy. 25. Cloudy: damp. 26. Bright: cloudy. 27. 

 Bright : shower. 28. Bright : cloudy. 29. Cloudy : showery. 30. Bright : 

 cloudy. 31. Bright. 



■dpplegarth Manse, Dumfries-shire. — May 1,2. Dry and withering. 3. Cloudy. 

 4. Fine. 5. Cloudy, with rain. 6. Showery. 7. Wet day. 8. Showers a.m. : 

 cleared. 9. Fair, but cool. 10. Fair, but threatening. 11. Showery. 12 — 17. 

 Fair and fine. 18. Fair and fine, but cloudy. 19. Fine rain p.m. 20. Rain 

 and hail. 21. Fair and fine. 22. Showery. 23. Showery: growing weather. 



24. Showery. 25. Fair and fine. 26. One shower : fine p.m. 27. Fair and 

 fine. 28. Fair till noon : then rain. 29,30. Showers. 31. Slight showers. 



Sun shone out 29 days. Rain fell 12 days. Thunder 2 days. Hail 1 day. 



Wind North-east 1 day. East 3 days. East- south-east 1 day. South-east 5 

 days. South-south-east 4§ days. South 5 days. South-west 4$ days. West- 

 south-west 4 days. West 1£ day. North-west 1£ day. 



Calm 7 days. Moderate 14 days. Brisk 2 days. Strong breeze 6 days. 

 Boisterous 2 days. 



