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this to you on a diagram. If I had made a diagram twenty-five 

 feet in diameter, it would only have amounted to half-an-inch on 

 each side. You must accept that as a thing which has been very 

 accurately calculated from theory; and the way in which it has been 

 determined from observation is this. If the earth is swollen out at the 

 equator, then the earth is flatter towards the poles than it is at the 

 equator: the bend of the earth is more rapid at the equator than 

 at the poles. We have great materials for arriving at a certain 

 conclusion on that point. That was the first thing in the remarkable 

 French experiment I mentioned, that is, — the relation of the bend at 

 Peru to that at Lapland. There have been many similar results, 

 but the best is that found by combining the great European arc 

 that goes so far north, and the Indian arc that goes so near the 

 equator. Generally speaking we have all agreed, and there is no 

 doubt that it is a general fact that the difterent parts of the earth 

 have those different degrees of bend. 



Now when in this manner, by the measurements of arcs, we 

 obtain the measures of the dimensions of the ellipsis of the earth, 

 and they agree so well with what we calculated on the supposition 

 that the mass of the earth is or has been fluid, it leads us at once 

 to the conclusion that the earth has been in a fluid state. Taking 

 the dimensions of the earth as measured upon the sea, there is very 

 little departure from those computed on the elliptic supposition. 

 There are mountains in some places, but a great extent of sea in 

 others, and islands are cropping up in all places ; and altogether 

 the form is not such as would-be taken by piling a number of 

 blocks for building any structure, but the form that would be taken 

 by a fluid mass carrying floating solids, and partially solidified 

 since the form was taken. But it has at some time been in a fluid 

 state. 



There is a curious thing which was brought particularly under 

 my notice some time ago during the Indian Survey. The Indian 

 arc begins at Cape Comorin, and goes through the whole length 

 of India past Delhi. It is a most remarkable arc in geographical 

 position. The officers used the instruments for the star- 

 observations at divers points on the line. They found these 



