VOL. XLVII.J PHILOSOPHICAL TRANSACTIONS. 271 



cavities appeared filled and covered with a mixture of hairy and stony particles; 

 whence he conjectures that it probably was the nucleus of the stone. Nothing 

 remarkable occurred during the cure, but that the patient, ever after the second 

 day from the operation, was capable of retaining her urine, and soon perfectly 

 recovered. 



LXXX. Of a Water-Sjjout, raised off the Land, in Deeping- Fen, Lincoln- 

 shire. By the Rev. Mr. Benj. Ray, of Cowbit near Spalding, p. 477. 



May the 5th, 1752, a phenomenon appeared about 7 in the evening, in Deep- 

 ing-Fen, which, from its effects, seemed to be a water-spout, broken from the 

 clouds. A watery substance, as it seemed, was seen moving on the surface of 

 the earth and water, in Deeping-Fen. It passed along with such violence and 

 rapidity, that it carried every thing before it: such as grass, straw, and stubble; 

 and in going over the country bank, it raised the dust to a great height; and 

 when it arrived in the wash, in the midst of the water, and just over against 

 where Mr. R. lived, it stood still for some minutes. This watery substance 

 spouted out water from its own surface, to a considerable height, and with a ter- 

 rible noise. 



On its second route, it proceeded in a side line into the river, breaking in its 

 passage a fishing-net, and there moved along, till it came to the church, where 

 it again stood a little while, and then made its next passage through the 

 space between the church and the parsonage house, towards Weston hills and 

 Moulton chapel. In its way to these places, it tore up a field of turnips, broke 

 a gate off the hinges, and another into pieces. Those who saw it evaporate, 

 affirm it ascended into the clouds in a long spearing vapour, and at last ended in 

 a fiery stream. There was a mist, like smoke, frequently round it. Three more 

 were seen at the same time in different places. 



LXXXI. Of Two Methods, by tuhich the Irregularity of the Motion of a Clock, 

 arising from the Influence of Heat and Cold on the Rod of the Pendulum, 

 may be prevented. By John Ellicott, F.R.S. p. 470. 

 The first of these methods consists in a particular construction of the pen- 

 dulum itself, which occurred to him several years before. About the year 1732, 

 an experiment, which Mr. Ellicott made to satisfy some gentlemen, that the rod 

 of a pendulum was liable to be considerably influenced by moderate degrees of 

 heats and cold, led him to consider, that as metals differ from each other in their 

 density, it was highly probable they might also differ from each other in their 

 expansion; and that this difference of the expansions of two metals might be 

 so applied, as in a great measure to remove those irregularities in the motion of 

 a clock, which arise from the effect of heat and cold on the length of a pen- 



