<?xml version="1.0" encoding="utf-8"?>
<rdf:Description rdf:about="https://catalogues.royalsociety.org:443/CalmView/record/catalog/MS/119/2/30" xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:dc="http://purl.org/dc/elements/1.1/">
  <dc:title>Letter from Charles James Buchanan Riddell, Woolwich to Humphrey Lloyd, Trinity College, Dublin</dc:title>
  <dc:description>Riddell has recently heard from [Frederick Marow] Eardley-Wilmot, and he has bought '12 yoke of oxen' in anticipation of the survey. Riddell informs Lloyd that his supplemental observatory is very compact and will send a description to [William James] Smythe and [Charles] Younghusband. 

Riddell has been working on a portable magnetometer, and has written a description of it along with instructions for adjustments. This is to be printed with Mr [Robert Were] Fox’s instructions for the use of his dip circle. 

Discussion on the declination arc which is to begin at once along with additional observations. Riddell discusses [Edward] Sabine’s comments on the topic.</dc:description>
  <dc:date>15 March 1842</dc:date>
</rdf:Description>