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great measures have been made ; and I am able to exhibit to you 

 upon this globe — for the use of which I am indebted to a Society- 

 similar to your own in East Suffolk — the principal lines that have 

 been measured in the north and south directions. There are 

 astronomical advantages in taking these measures in the north and 

 south rather than in any other direction. I only mention that as 

 accounting for the directions of certain lines, and those lines I have 

 laid down by pieces of paper upon the globe. 



Now, beginning from the East. The first is the Great Indian 

 arc, which extends from Cape Comorin to the neighbourhood of 

 the Himalaya mountains. The second is the greatest of all : it is 

 the Great European arc, which, by the united efforts of the Ger- 

 mans, the Russians, and the Swedes, has been extended from the 

 Danube to the North Cape. It is a prodigious arc. In calling 

 your attention to this map of the triangulation of Europe, I am 

 desirous of pointing out to you one line in particular. When you 

 come to look clearly at this map, you will see that over the greater 

 part of Europe the triangles are numerous, partly for the purpose 

 of territorial survey, and pardy for purposes like this — for the 

 dimensions of the earth. But beyond St. Petersbiug you see a 

 single chain of triangles, through the desolate parts of Norway to 

 the North Cape. It is a truly scientific and meritorious enterprise, 

 undertaken not for any territorial purpose, but solely for the 

 measure of the earth. It begins as a single chain at St. Petersburg, 

 and so goes on to the North Cape— a line of great extent. 



To make a recapitulation of the principal arcs measured. I 

 begin with that of India. Then there is this very long one, 

 through the East of Europe. The next is the French Arc, begun 

 during the height of the terrors of the French Revolution ; and it 

 is a most remarkable instance that that noble nation would, at the 

 most agitated time, turn their attention to Science. It starts from 

 a small island not far from Minorca, and extends to Dunkirk. 

 Observe that, as it was done before the others, its methods are not 

 quite so good as they are now. Then here is our English Arc, 

 which extends from Dunnose, in the Isle of Wight, to the 

 northernmost point of Shetland ; that is an arc of the highest 



