Celadon Leeds Daboll to Faraday   17 October 1863

Castle & Falcon Hotel. London | Saturday Evening Oct 17 / 63

Dr Sir

You will pardon the liberty I take in thus addressing you, but upon reflection this evening, several things suggest themselves to me relative to our conversation to day, which I deem it proper to communicate. You alluded to the current expense attending my fog apparatus. I told you the cost for fuel¹. The letter of Com. Powell², U.S.N. and L.H. Prospectus in New York which I loaned the Secretary, Mr Berthon, speaks I think, of the expenses attending the fog apparatus at New London Light House, as being, or having been but about twenty dollars (four pounds) during its operation for four years.

After the loss of the Anglo Saxon³, a few miles from Cape Race, a discussion took place in the House of Commons, here, as to whether the government had refused permission for the use of my fog signal at Cape Race, &c⁴. About that time I recd a communication from the Trinity corporation asking information in regard to my invention as at work at the New London Light House. Supposing that the Trinity Corporation had control of the L.H. Department of England, I determined upon bringing a practical working apparatus here, which would the better illustrate the invention, which I have done. This apparatus must speak for itself.

You will notice that Professor Henry concludes his report in these words. “The intensity of the sound may be indefinitely increased”. The Professor has, in this short sentence, practically illustrated a great scientific principle. A greater volume of air, and at greater pressure, or even the same pressure, when applied to the Enlarged mouth piece, and larger trumpet, will produce greater sound, such an apparatus it was proposed to erect at Cape Race.

One great principle in my arrangement moreover is, that it appears a continuation of sound, so that the same when heard, can be located by the pilot or navigator, and its direction marked by compass before the sound ceases. You will please bear in mind that when this signal was erected at the New London Light House, it was considered in the light of an experiment. Its application at a Light House was new. Four years practical working, and the testing of nautical men of unquestionable veracity, will best determine whether it has not fully established all that is claimed for it.

Though not gifted in science myself, my early tuition among nautical and mathematical men at my Father’s⁵ Academy, who for more than half a century taught all these branches, stimulated me to later experiment in steam and air for signals of warning upon the seabord [sic]. If my invention shall be the means of guiding the marriner [sic] in safety, and aiding to preserve life, I shall feel that my life has not been spent in vain. If not inconsistent with your views of propriety, I shall be glad to know your views of the practicality of my invention, or otherwise, as a Fog Signal for L.H. purposes -

I have the honor to be | - Very respectfully yours &c | C.L. Daboll

Professor Faraday, London.