Page:Philosophical transactions of the Royal Society of London 40.djvu/60

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the most Southern, has no others Bounds to the East than the East itself, if I may be indulged the Expression; seeing its Extent that Way contains near half the Earth?

Another great Advantage to be obtain'd by the Work I now propose to be made in Russia, is, That, we coming after others, shall reap the Benefit of all their Knowledge and Experience in the like kind of Measurements: Whence we may expect to succeed and execute it better than could have been done elsewhere, by applying timely Remedies against the Difficulties that occurr'd in other Places.

These Operations are to be founded on a Basis of the greatest Length possible; which must be actually measured, and with the greatest Exactness that may be; as it is to serve for a Foundation to the Measurement of all the Triangles. And in this Point too we have a very great Conveniency near Petersbourg, seeing on the Ice here we may measure out a Basis, greater than has been hitherto taken, namely, from the Coast of Ingria about Peterhoff, to the Coast of Finland toward Systerbeck. There is not less than 20 Wersts Distance between these two Extremities, and this great Distance may be measured very exactly, this Year especially, that the Ice is very even. Moreover, as this Basis is situate between the Isle of Cronstad and Petersbourg, in a Direction nearly perpendicular to the Distance from Petersbourg to Cronstad; there can be no better Method for inferring thence, by exact Observation of the Angles taken at the Extremities of this Basis, the Distance from the Centre of the Imperial Observatory to the Steeple of the new Church of Cronstad; which two Objects are seen reciprocally from each other, and are notless