Reference numberMS/119/2/44
TitleFirst half of letter from Charles James Buchanan Riddell, Woolwich to Humphrey Lloyd
Date5 January 1844
DescriptionDiscussion on the portable apparatus instructions. Riddell forwarded an extract of a letter from Lloyd to [Edward] Sabine regarding the inclinometer and mentions that Lloyd has adopted two iron bars. Discussion on the description of the instruments given in the portable apparatus instructions. Riddell notes the mirror appears to be more convenient than the collimator for small magnets. Riddell asks Lloyd about the dimensions of the iron bars, and the distance they should be from the centre of the magnet. Riddell asks Lloyd whether the method of adjustments and formula for computing the coefficient be the same as before.

Riddell lists the alterations to be made to the instruments in use in order to obtain the same construction. The alterations can be made without any difficulty. The spare stirrups of the small observatory instruments are furnished with azimuthal motion and can be used for this purpose.

[The second half of this letter is MS/119/2/45]
Physical descriptionInk on paper
Access statusOpen
Related records in the catalogueMS/119/2/45
Fellows associated with this archive
NA7327Riddell; Charles James Buchanan (1817 - 1903)1817 - 1903
NA8252Lloyd; Humphrey (1800 - 1881)1800 - 1881
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