Faraday to Peter Henry Berthon   12 October 1861

Royal Institution | 12 Octr. 1861

Sir

I reply to your letter of the 9th instant¹[.]

I understand that the Honble Major Fitzmaurice in regard to the light considers “a single Olefiant gas under all the circumstances necessary to be considered as the best adapted for a light house” and “retracts the others from consideration”[.]

In his letter of July 1860² there is reference to the selected lime light with gases in gasometers - to that with gases compressed into cylinders - to a grand life light - to a new patent Argand Olefiant gas burner - to a dioptric life light with three jets - to a Fitzmaurice gas light - to an Olefiant gas Argand light - to a Fitzmaurice New Argand Olefiant gas light - to some with oblong burners, to others with round burners. - and to others with three burners set triangularly[.]

There are no numbers or marks to these proposed lamps to distinguish them and I cannot tell whether the one now proposed as the best and remaining alone before the Trinity House is any one of those referred to or if so which[.]

Neither can I tell which of the answers (amounting to 20) given in that letter (if any of them) refer to the “single Olefiant gas” lamp now retained; neither can I tell or guess at its consumption of fuel;- or the shape & size of the burner and flame. The information is on the whole so confused that it is not fair to ask my opinion upon it[.]

But as it seems very difficult to obtain the data for an opinion I can only say that the practical proof must be the more strict and I might repeat the close of a letter I wrote to you on the 23 May 1861³ - in which I said in respect of one of Major F - propositions now withdrawn that I could “see no objection to his exhibition of the light experimentally in the lanthorn at Blackwall provided it be done in such a manner as to prove whether the light is available for light house purposes or not. In reference to that matter I may mention to you my letter to Major Fitzmaurice of 16 August 1858⁴ and mine to you of the 20th⁵ with a copy of the above and perhaps also mine to you of the 29th Septr. 1860”⁶ These references were to point to the many times on which I have asked for clear statements - and to shew the care which I think the Trinity House & their officers are bound to exercise in the matters which come before them.

Any light which claims to be superior to those in use for light house purposes should when brought before the T.H. be described as to its special nature or character - its form & general construction - its requisites out of the lighthouse - the necessary number of attendants - its practice in the lighthouse - its illuminating force in comparison with the central oil lamp which it is to replace - its permanence or liability to accident or interruption - & its expence:- both current & of outlay - and the inventor that cannot give such a description cannot tell whether his light is better or so good as those the TH already possess. After that has been done the light itself may be compared with the present oil lamp in any convenient place and does not in the present case need a lighthouse or the Blackwall lanthorn for the purpose;- after that (if it promises well) it may be tried in a light house as the Upper S Foreland, where the real & necessary practice can be tested and during that practice the light can be compared at sea & before all observers with a real lighthouse standard given in that case by the lower S. Foreland light. In the present instance if the written description & statement is not forthcoming the second & third steps cannot be dispensed with[.]

I cannot but feel at this time that there is a great deal of correspondence and much change & uncertainty in the propositions - that the time goes on but we make no practical advance with it⁷[.]

I am Sir | Your Very faithful Servant | M. Faraday

P.H. Berthon Esqr | &c &c &c