

32 



MATHEMATICAL and 



2; 



o 



# 



o 



O 



?^ 



<! 



4 



I 



3 



4 



Oiitunce ot the limbs of and $ in Chords pa- 

 rallel to the ^cjuator. 



H.M.Scc. 



3- 58. 53 

 4. 27. iJ5 



6. 4* 27 

 6. 9. aS 



In. 



o. 



I. 



^. 

 o. 



30thi5. 500t1l8. 



17. 14,3 E. limb 



3, 6 E. limb 



o. %o E. limb 



Ij. 6.5 W. limb 



M. Scc% 



7- 44,57 

 10. 14,74 

 18. 0,08 



6. 43» 7 



Panillaxes to the times of the 

 micrometer meafures. 



Seconds. 



17,0 

 18,16 



ao, 75 

 20,81 



Seconds 

 16,1 

 17,18 

 19,16 



i9>* 



Sccondb. 



5.40 

 5.86 

 8,06 



8,* 





Diameters of June 3, i~/(>^j. 



JTimc per clock 



A. M. 

 h. m. fee. 



8. 40. o 



?,. 45. o 



P. M. 



iz. 40. o 



f 



Micrometer 

 meafures. 



In. 20ths. jooths. 



3' 

 3 

 3 



3 

 3 



ir. 

 II. 

 II. 



II. 

 ir. 



13 

 16 



13 



13 

 la 



Value. 



m, fee, 

 31- 34iX6 

 31. 37,34 

 31- 34,16 



31- 



31. 



34,t6 



33>I 



Diameters of ^ taken on June 3d, 



1769. 



Micrometer 



meafures. 



In. 7,oths.5O0ths. 



Mean of the above 5 horizontal 

 diameters of - - - 

 Or leaving out the ad which differs 

 moil from the reft, and was judged 

 to be taken too large; the mean ot 



the other 4 'f^ 



31. 34,58 



31- :i:ii^ 



I'inic per 



clock. 

 h. m. fee. 



3. O. O 



3. a. o 



3- 4. o 



4. 15. o 



5- 55- o 



5. 5<^- o 



Value, 



o. 

 o. 



o. 

 o. 

 o. 

 o. 



a. 

 2. 





a. 

 2. 

 1 



4,6 



5.^5 



4,7 

 4,7 



5^33 



Sec. 



56,75 



57,^8 



57,44 

 56,91 



56,91 



57,53 



Mean of the above 6 for dia- 

 meter of ^ - - - - 



57,U 



Which srivcs O's fcmldianictcr 13'- 46," 9+ ! *^* '»' ""eficond tKnd ^ of a fccond larger than thu- 

 diamcter riven in the luiitical ahnanack for the tranfit day. Yet, Venus 5 diameter though 

 taken with tlir utmofl: rare by the fame micrometer and at the farne focus (a. thc_.Sun s) comet 

 out about one fecond Ids than it was expedcd, being 57",^! or about 1-33 of © s .hamcter. 

 The vertical diameter of on the fame day was 31'. 31", 8 at 4h. 40. J . M. 



Of the micrometer meafures, the 2d, 5th, and i8th 



diftance of the neareft limbs of the Sun and Faius ; the 

 I ft in a chord parallel to the equator, the ift and 6th of 

 the diameters of Fetius; and the ift and 4th of the diame- 

 ters of the Sun, were taken by Mr. Rittenhouie._ The 3d 

 and 1 6th diftance of the neareft limbs, the 3d diameter of 



Venus and the 2d of the Sun, were taken by Mr. Lukens. 

 All the other micrometer meafures were taken by myfelf, 

 while Mr.Rittcnhoufe applied himfelf totake the appiilfcs 

 of the limbs of the Sun and center of Venus to the crofs 

 hairs of his equal altitude inftrument, Mr. Lukens writing 

 down the obfervations and their cxad time. 



The micrometer meafures were all feparately reduced to 

 their value in minutes and feconds by Mr. Rittcnhoufe, 

 and by myfelf, making the proper allowance for the error 

 ofadjuftmentof the inftrument. Many more micrometer 

 meafures might have been taken j but had we inade the 



Intervals 



\1 



1 



ft-- 









T 

 t 



1 



r 



l 



