Reference numberMS/119/2/35
TitleLetter from Charles James Buchanan Riddell, Woolwich to Humphrey Lloyd
Date8 December 1842
DescriptionRiddell informs Lloyd that [Henry] Barrow, [Thomas Charles] Robinson’s successor, has been ordered to make a set of instruments for Mr [Gucke], like those sent to the Antarctic expedition. Barrow will be visiting Woolwich to see the instruments and receive directions. Riddell has written down particulars in which it is advisable to depart from the original and would like Lloyd to look over this and return with his remarks.

Discussion on the length of the magnets. Riddell discusses the force of the magnets of different lengths at different observatories currently operating. Riddell notes that [Samuel] Jones has made a stirrup for one of the larger magnets similar to the transportable.

The adjustments will be structured using the plummets. Riddell has omitted the collimator tube for the bifilar.

Riddell informs Lloyd that he has received the small magnets sent by Lloyd, which Riddell hopes to magnetise soon.

Discussion on the inclinometer’s observations. Riddell mentions attaching the deflecting bar scales to the small declination magnetometer. Discussion on the portable declinometer, used for the absolute declination and observations of vibration.
Physical descriptionInk on paper
Access statusOpen
Fellows associated with this archive
NA7327Riddell; Charles James Buchanan (1817 - 1903)1817 - 1903
NA8252Lloyd; Humphrey (1800 - 1881)1800 - 1881
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