To Charles Lyell 21 April [1856]
Summary
Speculates about cause of inclination in unusual columns of lava. Suggests CL check with William Hopkins about sliding movements in viscid matter.
Comments on CL’s expedition to Madeira.
| Author: | Charles Robert Darwin |
| Addressee: | Charles Lyell, 1st baronet |
| Date: | 21 Apr [1856] |
| Classmark: | American Philosophical Society (Mss.B.D25.126) |
| Letter no: | DCP-LETT-1855 |
