154 Mr. W. F. Miller, Dates of the 



varies in thickness near London ; it is 147 ft. in the Streatham 

 Well, 340 ft. in the Caterham Well ; but 250 ft. would probably 

 be a fair estimate for the thickness at Addington, so that the 

 probable depth to the Lower Greensand would be some 750 ft. 



To revert to the well; water was first found at a depth of 

 87 ft. from the surface, or 231 ft. above sea-level, and at 101 ft. 

 pumps had to be started to keep the well sufficiently free for 

 carrying on the work. The greatest yield of water during the 

 progress of sinking the well was 196,000 gallons daily. On the 

 10th of April, 1887, after the galleries had been pierced, the 

 yield was 2,491,000 gallons, and as the available pumping 

 capacity was overpowered, work in the well ceased. Meanwhile 

 the water as it was raised was conveyed through pipes to the 

 road through Addington, by the side of which it flowed to a 

 gravel-pit at Kent Gate, where it soaked away in the porous 

 ground. After pumping had been discontinued for a year, 

 measurements of the water in the well gave the following 

 results : — 1888, April 4th, depth from the surface, 92 ft. ; April 

 25th, 87'4 ft., the heights above O.D. being respectively 226 ft. 

 and 230-6 ft. 



69. — Dates of the First Flowerino of some Plants near 

 Croydon, 1880 xo 1887. 



By William F. Miller. 



(Bead September 12th, 1888.) 



Most of the members of the Club are, I expect, aware of the 

 good work done for many years by the Rev. T. A. Preston, 

 formerly of Marlborough College, in the way of tabulating and 

 arranging, for the Eoyal Meteorological Society, phenological 

 observations relating to the dates of the first flowering of plants, 

 the first appearance of migratory birds, and other allied phe- 

 nomena. These dates vary very much from year to year, and 

 Mr. Preston and those observers with whom he is associated 

 have felt that by the accumulation of carefully noted facts of this 

 description, considerable progress would be made in our acquaint- 

 ance with the annually recurring features of Nature. 



My own observations have been confined almost exclusively to 

 plants. They were commenced before I knew of Mr. Preston's 

 labours, but the results have been of late years embodied in his 

 reports, our Croydon district being one of the nineteen stations 

 included in his survey. It is only right, by the way, to note that 

 the observations of most, if not all, of the observers do not 

 profess to be more than approximately correct. A perfect 

 observer would be one who, having first carefully mapped out a 



