My dear Backy

It is grand about the Pelargonium leaves & seems to me a most curious subject to investigate.¹ I think that I will endeavour to see Frankland & see what he can suggest.² It seems to me that you ought now to ascertain whether any alkali comes from leaves without glands or Hairs, & secondly whether the elimination is connected with the action of light, excluding every ray.³

If you can decide anything before we go let me hear. If I see Frankland, it will be on Monday or Tuesday. Boussingault⁴ statement that salts pass into leaves has some bearing with your discovery that they pass out of leaves.— With plants not exposed to rain & not syringed out, there ought to be potash on the surface, so that if many leaves were rapidly washed & the water evaporated almost to dryness, these ought to be alkaline. Can the good of syringing be in part to wash off the excreted matter?⁵

Have another go with radicles of Horse-chesnut— These are far more important than Spanish chesnut for me.—⁶ In the study there is basket with Horse-chesnuts put all of them to soak for 36^o & then put onto tin-boxes in Hot-House for germination.—

Tell abbadubba⁷ that Baba sends him a kiss.

yours affect | C. D