116 LEUSTH OF THE SOLAR YEA3.. 



occupying the weft, at leaft at intervals, as in Wales, CaiU* 

 ' berland, and Galloway. Further to the north, that is, beyond 

 theTay, the ftrata became entirely primitive, mofl of them of 

 the denfeft kind, and in the interior of the ifland, with a very 

 few cxeptions, continue the fame to its moft northern extre- 

 mity. In the furvey of Britain, therefore, feveral fituations 

 inuft occur where the plummet, pafliiig from lighter to denfer 

 ftrata, ought to give indications of fome irregularities in the 

 direction of tlie gravitating force. It will be feen hereaftet 

 how far thefe conjedures are verified by experience. 



(To he continued,) 



IV. 



On the Determination of the Length of the Solar Year, By Mr, 

 R. Winter. 



Red Crofs tVharf, London-Bridge, 

 13th Jan. 1804. 



To Mr. NICHOLSON, 

 SIR, 



Determination ^HOULD you confider the following communication as de- 

 of the length of ferving a place in your valuable Journal, by inferting it you 



Adual years. Will obhge 



\,, Your's, &c. 



R. WINTER. 



To determine the precife length of the Solar Year is an ob- 

 je6l of primary utility in aftronomy, as being the bafis for af- 

 <;ertaining the periods of all the moving bodies in the univerfe. 

 , Various and accurate methods have been given for deter- 

 mining this period; but as the following unites fimplicity, to 

 the advanced ftate of fcience, thefe chara6lers may render it 

 worthy of your con fi deration. 



Given, the time and place of the fun in the ecliptic, and the 

 time of its returning to the fame place; the obliquity of the 

 ' ecliptic for the prefent time, together with the decreafe there- 



of, ptjr year, to find the length of the folar year. 



According to Ptolemy, the place of the fun was Sagittarius 

 i^o 22' 50'^ anno. 130, Dec. l^th. 11^' 3S»* 40- (reduced to 



the 



