136 A/>. PiGOTT*s Ohjervations^ &:c. 



tudes, and for that purpofe had in 1776 divifions engraved on 

 the eye- tube of a refraftor ; but found tliat its high magnify- 

 ing powers prevented ftars of the firfl and fccond magnitude 

 becoming invifible. 



Laflly, I am inchned to think the following method pradi«» 

 cable, vi%. to refle£l in a telefcope, by means of an illumina- 

 tor, different degrees of light in a known proportion, fo that 

 ftars of all magnitudes may be obliterated. 



The changeable ftate of the weather will perhaps be thought 

 a confiderable obftacle to thefe contrivances, and to throw doubt' 

 •on the obfervations ; but this may be fufficiently obviated by 

 attending to fmall telefcopic ftars, which according to the 

 clearnefs of the atmofphere are more or lefs diftinftly feen. 



I beg the favour of you, dear Sir, to prefent thefe obferva- 

 tions to the Royal Society ; and believe me, with the greatefl 

 regard, &c. 



York, Dec. 5, 1784. EDWARD PIGOTT. 



