Reference numberMS/119/2/48
TitleFirst half of letter from Humphrey Lloyd, 17 Fitzwilliam Square, Dublin to Charles James Buchanan Riddell
Date8 January 1844
DescriptionLloyd apologises for not replying to Riddell’s letter at once but notes reviewing his papers there was nothing of note to mention.

Discussion regarding the observations at several deflecting distances employed for the determination of the coefficients. Lloyd mentions Lamont’s method, and discusses where he differs from Lamont and Riddell, which is the expediency of employing a third term of the series. Discussion on the distances being small in Lamont’s method of observations. Lloyd would prefer large distances, and then fix for that purpose.

Lloyd discusses another method of determining the coefficient not limited to any precise length of the magnet, but Lloyd does not find this method to be accurate for a fixed observatory when large magnets are used.

Lloyd discusses Riddell’s definition of P and Q, and notes they are constants.

Lloyd hopes Riddell’s trip to Germany was well.

Lloyd informs Riddell that the only fault he has with Riddell’s arrangement is that it is too ‘elaborate’. Riddell requires five instruments for his travelling observatory, whereas Lloyd would recommend only two. Lloyd advises that the simpler the instructions the and manipulations the better they will be received.

[The second half of this letter is MS/119/2/47]
Physical descriptionInk on paper
Access statusOpen
Related records in the catalogueMS/119/2/47
Fellows associated with this archive
NA8252Lloyd; Humphrey (1800 - 1881)1800 - 1881
NA7327Riddell; Charles James Buchanan (1817 - 1903)1817 - 1903
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