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1 20 



M A T H E M: A. T I G" A L a kb 



pbia and Norriton, fo is the length of a degree of long, at 

 the middle point (viz. 284869,5 feet) lo the length of a deg. 

 in mean lat. between Norriton and Philadelphia, the refult 

 was got 52^^13; being only thirieen hundreth parts of a 

 fecond of time more. 



The above account of the work was thoilght proper, that 

 thofe who will take the trouble may examine and corrcd 

 it if in any part neceffary. 



ijl 17,. 177a 



WILLIAM 



t.^ 



To //?^ American Philosophigal- Society, held at 



Philadelphia for promoting ufef id knowledge.- 



Gentlemen, 



GREEABLE to the order of laft meeting, we have 



y 



colleded into one general and fhort view (from the 

 laft, or 59th vol. of the philof tranfadions), the following- 

 account of the different obfervations of the late tranfit of; 

 Venus made in Europe and other diftant places; contain- 

 ing the apparent times of the contads;, the latitude and 

 longitude of the places of obfervation, fo far as known to 

 us, with fuch other circumftances, as we judged proper, 

 for anfwering the end you had in view; namely the afford- 

 ing materials to perfons of a curious and mathematical, 

 turn, who might be defirous of enquiring what parallax, 

 of the Sun, may be deduced from a comparifon of thefe 

 diftant obfervations, with thofe made in this Province, by 

 your appointment. 



Wc 



William Smith, Hugh Wil 



& 



occ. 



Nov. \Uh 1770. < T 



Thomas Combe, 



(3wEN Diddle, D. Rittenhouse, 



Apparent ihnes cf the CONTACTS of the Vnnhs of the SUN ^?i./ VKNUS; -ivUh oihcr clrawijlances of 

 vvfinoie^ In the d'iprsnl IVJROPKAN Okskrv^TION 3 <///ji' TRANSIT, Juue ^d^ 1769.. 



.. lat. 51*^. 3C^ 50'' N.lon. 25' of time * Weft. By Mr. HorffiU^, 

 ith a Gregorian rcfletSlor; nuig. power lOO times. 



MIDDLE TKMI»LE. 



with 

 h. 



7- 

 7* 



m. fee. 



II. 5^ A penumbra oljfcrvcd to {Irilteluto Q'slimb. At V more, viz-. 



II' I3'4 ? ^'^^^ maik a vifible dent aoar the vertex of 0's limb.- 



^t, 49^- internal contat^. 'I'Jie liglit jufl; clofuig round $ . 



* I'hc different longitudes are fet down in time, £all or Weil with refpeel to the royal oh.- 

 fci-vatory of Greciiwich,. as the firfl meridian. 



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