XX1Y 
PROCEEDIN'GS OF THE 
mean levels during tlie past year and each, of the other five years, 
he got 191 2 as lowest, and 192*3 as highest above the level of the 
sea. He preferred to take the level from the sea, because he knew 
of no other satisfactory datum to work from, as the surface of the 
land varied so much. Eut they had one constant datum in the 
mean height of the sea, and as it sufficed in speaking of the height 
of mountains, so he thought it might in speaking of the height of 
water in wells. From the figures he had given they would see 
that there had not been a mean variation per annum of much over 
one foot in the height of the water in his well for some six years. 
He also found, as did the author of the paper, that the general 
plane of saturation in the neighbourhood, into which the tube 
called a well dips, goes on rising until about the end of February 
or March, sometimes the beginning of April, and that the time at 
which the water is lowest is commonly October or November. Then 
begin the winter rains, and they go on saturating the ground, and 
the highest level of the water is commonly reached about March in 
this neighbourhood. 
Another question arose, and it was one frequently asked though 
not touched upon by the author of the paper, as to how long it 
takes for the water which falls on the surface to get down to th£ 
plane of saturation. That depended upon the distance, and, for his 
own neighbourhood, where there were about twenty wells, the 
distance was 80 feet. It would be seen at once that, during the 
summer, the rain which falls on the surface does not get down to 
the stores below at all. The sun dries the surface, and the rain 
penetrates only a short distance, and dries out again. In January 
or February, however, with the amount of rain that has fallen 
during the earlier part of the winter, the whole of the soil down 
to the plane of saturation becomes wet, and a heavy rainfall 
will make itself felt in the rise of water below in the course of two 
or three hours. He did not mean to say that the rain which then 
falls goes down directly to the stores below; it acts according to 
hydraulic laws, and the water already saturating the earth is 
pressed down by that which falls on to the ground, and it is in 
that way, by the transference of water pressure through the in¬ 
fluence of the rain then falling, and not at once by the rain itself, 
that the water-level is raised. 
He should like to support what the author said with regard to 
the importance of records, particularly as to the nature of the soil 
and the distance from the surface to the plane of saturation. From 
these and other causes the variation must be very great, and there¬ 
fore it is not until observations are made by one person for a 
number of years, and comparisons are made between the observa¬ 
tions of different persons, that they would be able to generalise and 
to get an useful record of the flow; and general conditions of the 
stores of water below, on which we all depend for our daily supply. 
Prof. Attfield then briefly described his apparatus. He said that 
a post eight or ten feet high was fixed immediately above the well. 
It was surmounted by a pulley. Over the pulley passed a chain, 
