To J. F. W. Herschel 13 May 1843

My dear Sir John

I am quite guiltless of the Camomilic recipe, I can assure you; & know not who may have taken my name, as it seems, to my credit - thus unduly obtained. The Wasp cure I can certainly lay claim to, & you will find it a very efficacious remedy. I employed it for the sake of procuring specimens of Wasp-nests. My plan was to place (at night) a small saucer of spirits of turpentine close to the hole & invert a flower pot over the hole & saucer, taking care to earth it round & stopper the hole at the bottom of the pot. I dug up the nests in 36 hours afterwards often found to answer this purpose. I have known a neglected non-flowering Cactus suddenly form a multitude of flowering buds. It was over-luxuriant till it was allowed to remain without water for a longer time than usual. In the E. Indies, the roots of some of our fruit trees are occasionally exposed for a time, when they are over luxuriant & produce none but leaf-buds, & the check thus given them induced the development of flower buds. I do not think that in general salt seems to be of much value as a stimulant to vegetation. If used, it should be in small doses. Guano is of universal use. I think it is recommended to add a pound to 4 gallons of water for garden purposes - & again to add 4 gallons to the same for obtaining a second dose of liquid manure. I saw this also in the Gardeners Chronicle last year. I have no idea where you can procure plenty of Deodar seeds - but I will ask Lindley when I happen to write to him as I shortly shall & I have no doubt he can tell me. I shall be very much obliged by a copy of the paper you refer to on the action of light on vegetable colours. If sent to my Brother's address in London I shall get it - or he can send for it wherever it may be convenient for you to leave it.

S. W. Henslow Ese 13 Clements Inn

I have only Saturday morning for a holiday whilst here, or I would have replied earlier.

Believe me

very truly yrs

J. S. Henslow