Jacob Herbert to Faraday   27 August 1845

Trinity House London | 27th August 1845.

Sir,

Mess: Briggs1 & Garford2 having in the early part of this year, drawn the attention of this Corporation to the Refined Rape Oil manufactured by them, trials of the burning qualities of that Oil have since been made at this House3, the result of which, when the Oil has been burnt in the patent lamp of Mess: Wilkins & Ken[d]rick4, has been so satisfactory, as to induce the Board to entertain an expectation, that the said Lamp and Oil may be economically, and possibly otherwise advantageously, used in the illumination of Light Houses; but previously to giving any directions for their introduction to the Light Houses, except for limited experimental trial, they are desirous of bringing the subject under your notice, with the object of obtaining your opinion on the two following important points, viz:-

1st The power of the Light produced by the combustion of the said refined Rape Oil, in the said patent Lamp of Mess: Wilkins and Ken[d]rick, as compared with the power of the Light produced by the Combustion of pure Sperm Oil in the ordinary argand Lamp in use at this Corporations Light Houses.

2nd The comparative horizontal divergence of the parabolic Reflector used in the Trinity House Light Houses in conjunction with the patent Lamp of Mess: Wilkins & Ken[d]rick burning the said refined Rape Oil, and when in conjunction with the Argand Lamp before mention'd burning pure Spermaceti Oil.

Altho' the Board state these as the two points to which they specifically direct your attention, it will be satisfactory to them to receive any remarks with which you may favor them, as resulting from observations which may be incident to, or connected with the experiments which you may make consequent upon this reference.

Mess: Wilkins will be instructed to furnish you with the Lamps and Reflectors which you may require, and in your informing me of the Quantities of the Oils which you would wish to have, they shall be sent to you, that is to say, the Sperm from the Corporation's Store at Blackwall, and the Rape Oil direct from Mess: Briggs & Garford the manufacturers.

I am, | Sir, | Your very obedient Servant | J. Herbert

M. Faraday Esqre.

1
Henry Briggs & Co, seedcrushers of 5 Primrose Street, Bishopsgate. POD.
2
John Garford & Sons, seedcrushers of Limehouse Hole. POD.
3
Trinity House By Board (Minutes, 15 July 1845, GL MS 30010/34, pp.463-4) set up a committee to examine the refined rape oil. This committee reported to the Board (Minutes, 26 August 1845, GL MS 30010/34, pp.491-2) who then referred the matter to Faraday.
4
Matthew Samuel Kendrick (otherwise unidentified) and Wilkins had been granted a patent (number 8486) on 28 April 1840 for "Improvements in lighting, and in lamps".

Please cite as “Faraday1770,” in Ɛpsilon: The Michael Faraday Collection accessed on 27 April 2024, https://epsilon.ac.uk/view/faraday/letters/Faraday1770