174 ACCOUNT of a SINGULAR 



the moon ; the altitude of its oppofite Umb was 14° ; fo that 

 its diameter fubtended an angle of no lefs than a hundred and 

 twelve degrees. 



The diameter of the fmall halo, 'which appeared to be a per- 

 fe(5l circle, with the moon in its centre, I found, after repeated 

 trials, was under 12*, and more than 8° ; but as the different 

 diameters of the large halo were not meafured, it cannot pofi- 

 tively be affirmed that it was an exadl circle ; on the contrary, 

 its limb did not feem to interfed the fmall circle quite fo much 

 at right angles, as the circular arch delineated in the plan. It 

 may therefore have been fomewhat eliptical. 



The fmall circle was remarkably bright, particularly at Weji 

 Rejlon, about five miles to the northward, the only other place 

 where the halo was obferved, and where it was thought to fend 

 forth flame. The fmall halo alfo continued there much long- 

 er than here, where fome thin fleecy clouds foon put an end to 

 it, but the large halo continued with us near an hour. 



The weather about this time was, for the feafon, remark- 

 ably mild, partictilarly on the day of the halo. The fky was 

 pretty clear all that day, and alfo in the evening ; but at the 

 time of the halo there was a fmall degree of hazinefs, particu- 

 larly towards the north, which did not however prevent the 

 moon from fliining with brightnefs ; and the ftars were even 

 vifible within the circle of the fmall halo ; there was little or 

 no wind. ^ 



The circles or belts of both halos are reprefented in the plan, 

 nearly of their apparent breadth, or perhaps a little broader ; the 

 light of both was whitilh, and confiderably bright, without co- 

 lour ; that of the large circle was the paler of the two, particu- 

 larly where it pafTed through the fmall circle : to the northward 

 it was fomewhat obfcure. 



By means of the angles taken as above, after having afcer- 

 tained, on a vertical circle of the heavens, the fituations of the 



moon. 



