432 On an eWtng and flowing Stream at Bridlington. 



element of the same kind as that of the excited surface was re- 

 pelled into the air; but the other remained upon the surface of 

 the ball. The tube being remc'ed, the electrometer, No. 2, be- 

 came permanently electrified, but in a state contrary to that of 

 No. 1. 



From the two different electrical states of the electrometers, 

 with and without the brass ball, it will be easily imdcrstood, that 

 there is a certain construction of the instrument which will not 

 remain permanently electrified. When the surface of the ball is 

 equal to the surfaces of the two leaves, all electrical signs will 

 vanish as soon as the excited surface is removed. 



Exp. 8. From some papers lately published in this Maga- 

 zine, it appears that the properties of the pith -ball electrometer 

 are not clearly understood. To satisfy myself in this particular, 

 I laid a thennometer-tube upon an insulating stand in a hori- 

 zontal position, and hung a pith-ball electrometer upon it near 

 one of its ends. These balls being immersed in an atmosphere 

 of thermogen diverged with that element. 



But when I fixed a brass ball upon one end of the glass tube, 

 ivith a pith-ball electrometer attached to it, and immersed the 

 balls in an atmosphere of theimogen, they diverged, but in a 

 contrary electrical state, for the reasons given in the two last 

 experiments. 



Lynn, May U, 1G15. Ez. WaLKER. 



[To be continued.] 



LXXV. On an ehhing and flowing Stream discovered ly loring 

 in the Harbour of' Bridlington. By John Storeu, M.D. 

 Communicated by the Right Hon. Sir Joseph Banks, Bart. 

 K.B.P.R.S.'^ 



J. HE following account of certain peculiarities attending a 

 spring of fresh water, which was tapped in boring within the 

 harbour of Bridlington quay, Yorkshire, is given from repeated 

 observations made during a residence of some weeks there, in 

 the months of July and August 1814. The harbour of Bridling- 

 ton quay is dry at low water, except for a rivulet v.-hich traverses 

 its bed: at high vvater^ it has from fifteen to seventeen feet of 

 water. 



Mr. Rennie, civil-engineer, was consulted in the year 1811, 

 respecting certain improvements projected in that harbour. At 

 his desire, with a view to ascertain the depth of the stratum of 

 clay in the harbour, the boring, which terminated in forming the 



* From the Pliilcsophical Transactions for 1815, part i. 



well 



