Meteorological Observations. 431 



Wilson and others as "the enchanted rock," consists of a rather coarse- 

 grained granite. I obtained specimens of the granite from some friends 

 of mine who were on the spot, and ascertained also that beds of 

 limestone extended to the very base of the rock. This fact, in con- 

 nexion with the other one, that on the San Saba river, sih'^r-mines 

 have been worked formerly by the Spaniards in a plutonic rock, seem 

 to lead to the supposition that here, on the tributaries of the Colo- 

 rado, we arrive at the boundary where the stratified rocks of the east 

 side of the continent come in contact with the crystalline masses of 

 the Rocky Mountains. If this supposition is correct, it follows that 

 the cretaceous formation is the only one of the whole series of stra- 

 tified rocks which exists in this part of Texas. From the facts ob- 

 served in Texas, we derive additional confirmation of the hypo- 

 thesis long since made with great sagacity by M. Leopold von Buch 

 and never refuted, that the oolite series of Europe have no equivalent 

 on the American continent. 



In the course of this summer I hope to extend my investigations to 

 other parts of the country, and may be able then to give your readers 

 some more satisfactory information about its geological relations. — 

 Sillitnan's American Journal, Nov. 1846. 



METEOROLOGICAL OBSERVATIONS FOR APRIL 1847. 

 Chiswick. — April 1. Sb'ght haze : sleet and hail-showers: frosty. 2. Overcast. 

 3. Cloudy and cold : rain. 4. Overcast. 5. Cloudy : fine. 6. Cloudy : rain at 

 night. 7. Cloudy : rain. 8. Rain: cloudy: clear. 9. Clear and cold. 10. 

 Cloudy: fine. 11. Uniformly overcast : rain. 12. Rain: cloudy. 13. Densely 

 clouded. 14. Bleak and cold : slight hail -showers. 15. Snow and hail : clear, 

 cold and dry : sharp frost at night. 16. Sharp frost : clear and cold. 17. Frosty 

 and foggy : cold and dry. 18. Clear. 19. Clear: cloudy: slight frost. 20. 

 Foggy : fine, with sun : cloudy. 2J. Clear: overcast. 22. Cold haze : frosty. 

 23. Fine : clear at night. 24. Slight haze : fine, with sun : frosty. 25. Foggy : 

 fine. 26. Rain : overcast. 27. Boisterous, with showers. 28. Fine : showery. 

 29. Heavy showers, partly hail : thunder. 30. Clear : heavy clouds and showers. 



jVlean temperature of the month 44°-28 



Mean temperature of April 1846 47 '36 



Mean temperature of April for the last twenty years ... 47 "20 

 Average amount of rain in April 1 '47 inch. 



Boston. — April 1. Cloudy: snow a.m. and p.m. : rain yesterday. 2. Cloudy: 

 large fall of snow a.m. : rain p.m. 3. Cloudy : snow a.m. : rain p.m. 4 — 6. 

 Fine. 7. Cloudy. 8. Rain : rain early a.m. : stormy, with rain p.m. 9. Stormy. 

 10. Fine. 11. Fine: rain a.m. and p.m. 12, 13. Cloudy. 14. Fine. 15. Cloudy: 

 snow-showers. 16. Fine. 17,18. Fine : ice this morning. 19. Cloudy. 20 — 

 23. Fine. 24. Fine: rain p.m. 25. Cloudy: rain and hail p.m. 26. Rain: 

 rain a.m. 27. Windy : rain p.3i. 28. Windy. 29. Fine. 30. Cloudy: thunder 

 and rain p.m. 



Sandwick Manse y Orkney. — April 1. Snowing: snow. 2. Snowing: showers: 

 snow-showers. 3. Cloudy. 4. Bright: damp. 5. Sleet-showers: showers. 

 6. Bright: showers. 7. Bright: hail-showers: aurora. 8. Rain: showers. 

 9. Showers : clear : aurora. 10. Clear. 11. Clear : rain. 12. Bright : cloudy. 

 13. Snow-showers : cloudy. 14, 15. Cloudy. 16. Clear : cloudy. 17. Showers: 

 clear. 18. Showers: cloudy. 19. Fine : clear. 20. Showers: clear. 21. Cloudy: 

 clear : frost. 22. Bright : cloudy. 23. Bright : showers. 24. Showers : drops. 

 25. Bright : cloudy. 26. Bright : clear. 27. Bright : rain. 28 Showers : 

 drizzle. 29, 30. Bright : clear. 



