Copy letter from Robert William Frederick Harrison, to Dr Robert Alfred Lehfeldt Harrison cannot further the matter of Lehfeldt's note on the "Joule-Kelvin Effect" because of the rule that before any Paper is considered by the Royal Society it must be communicated by a Fellow. He suspects that Lehfeldt will be able to find a Fellow willing to further his note, but offers to assist if he is not successful. If he has not kept a copy he should let Harrison know as he will need it to show when proposing that a Fellow communicate it. 10 February 1904