To J. D. Hooker   19 August 1873

My dear Hooker

The next time you walk round the garden ask M^r Smith¹ or any of yr best men what they think about injury from watering during Sunshine.

One of y^r men viz M^r Payne at Abinger, who seems very acute, declares that you may water safely any plant out of doors in sunshine, & that you may do the same for plants under glass, if the sashes are opened.² This seems to me very odd, but he seems positive on the point; & acts on it in raising splendid grapes. Another good gardener maintains that it is only cold water dripping often on the same point of a leaf that ever injures it.. I am utterly perplexed, but interested on the point. Give me what you learn when you come to Down³

yours affectly | Ch. Darwin

I sh^d like to hear what plants are believed to be most injured by being watered in sunshine, so that I might get such. I expect that I shall be utterly beaten, as on so many other points; but I intend to make a few experiments & observations.— I have already convinced myself that drops of water do not act as burning lenses.