SteavensonW. H., “A peep into Herschel's workshop” and “Catalogue of instruments made and (or) used by Sir William Herschel, as preserved at Slough and examined there in 1924, May and June”, Transactions of the Optical Society, xxvi (1924/25), 210–20, 221–38.
3.
For full details of the construction and use of Dall testers, see DallH. E., in Amateur telescope making (New York, 1953), 149–53, StoltzmannD. E. and HatchM., “Extensions of the Dall null test”, Sky & telescope, lii (1976), 210–14, and CoxR. E., “Additional notes on null testing”, ibid., 215–16.
4.
LubbockConstance A., The Herschel chronicle (Cambridge, 1933), 68.
