Faraday report to Trinity House   20 November 1860

Report on the South lighthouse at Whitby

Royal Institution, | 20th November 1860.

The adjustment of this Lighthouse has been completed by Mr James Chance¹ according to the instructions received from the Trinity House:- the lenticular part from a common focus 27 or 28mm above the burner - the upper reflectors from a common focus 28mm up and 30 aside & the lower reflectors from a common focus 25mm up and 40 aside; the mean ray being sent to the Sea horizon. The only exception is in the north lenticular panel the sea horizon focus of which is 25mm above the burner. The present condition of the experimental investigation of the lenticular part of the apparatus makes me not sorry for this circumstance.

The character of the lamp & its flame is most essential. The latter ought to be well watched and cared for. I find it very difficult to devise a sure check on the attendance. A pint & a half (or somewhat more) of oil ought to be burnt every hour in a first order lamp with a brilliant flame[.] But it is difficult to found an effectual check, either upon the quantity of oil which disappears or upon the time of the keepers visits to the lamp[.]

I have not seen the lighthouse since the adjustments were made; but they were made by Mr. James Chance himself and I have the fullest trust in him. I enclose his report[.]

Every thing thus far confirms me in the opinion that what the Trinity house has done in this case has been done well;- that every future case can be considered in relation to the adjustment necessary for it from the very beginning;- and that that adjustment can be carried out with certainty².

M. Faraday

20 Novr. 1860