VOL. LXXI.] PHILOSOPHICAL TRANSACTIONS. 117 



fresh breeze, could not be much less than 25 leagues in 15 hours, the distance 

 of time between the two observations of the heat, and hence the breadth of the 

 stream may be estimated at 20 leagues. The breadth of the Gulf of Florida, 

 which evidently bounds the stream at its origin, appears by the charts to be 2 or 

 3 miles less than this, excluding the rocks and sand-banks which surround the 

 Bahama Islands, and the shallow water that extends to a considerable distance 

 from the coast of Florida ; and the correspondence of these measures is very re- 

 markable, since the stream, from well-known principles of hydraulics, must 

 gradually become wider as it gets to a greater distance from the channel by which 

 it issues. 



XIX. On the Appearance of the Soil at opening a Well at Hanby, Lincolnshire. 

 By Sir Henry C. Englefield, Bart., F. R. and A. S. p. 345. 



The spot on which the well was sunk is nearly on a level with Lincoln Heath? 

 and of course high ground compared with the fen, which is distant from it above 

 6 miles. The soil was uniformly a blue clay, in parts rather inclining to a shaly 

 structure, and contained many casts of tellinse, a very little pyrites, and some 

 few small, but very elegant belemnites. These are all the usual fossils of clay ; 

 but what Sir H. thinks without example is, that through the whole mass of clay 

 were interspersed nodules of pure chalk, evidently rounded by long attrition, and 

 of all sizes from that of a pea to a child's head. They lay in no sort of order 

 that he could find. How deep this appearance might have continued he 

 could not determine, but no water having been found at the depth of 30 feet, 

 the trial was given up, as the expense would have exceeded the advantage 

 proposed. In all the environs there is not the least trace of chalk in any form 

 whatever that he could discover or hear of. 



XX. Astronomical Observations, by Nath. Pigott, Esq., F. R. S. p. 347- 

 In 1778 and \77Q Mr. P. observed in Glamorganshire; and by 35 meridian 

 observations of the sun and stars, all agreeing within 12 s from the mean, he de- 

 termined the latitude of his observatory at Frampton House 51° 25' I" n. And 

 its longitude, by comparison of many observations of the eclipses of Jupiter's 

 satellites, was 3° 29' 30* west of Greenwich. Frampton House lies between 

 Cowbridge and Lantwit ; about 4 miles south' of the former, and 1 mile north of 

 the latter, and about 2 miles from the Bristol channel ; and is nearly under the 

 same meridian as Watchet, a market town in Somersetshire. 



In the beginning of 1778, the declination west of a magnetic needle of 4 

 inches, made by Mr. Dollond, appeared to be 22° 1 1'. 



