XL. ' HYDRAULIC ASPECT OF THE ARTESIAN PROBLEM. 
We shall omit all-reference to the solution of Laplace’s 
equation, and the application of the method of conjugate 
functions or conformal transformation,’ remarking simply 
that in many cases one must be content to assign a value 
to the potential function and then determine the boundary 
conditions which will render the proposed function a true 
solution. 
The following are a few cases of interest. 
In Fig. 5, suppose A to be a point (‘source’) where a 
liquid is supplied to a stratum of indefinite area, and B a 
point (‘sink’) out of which it flows, then the flow will take 
place along the system of dipolar circles. These theoretical 
results can easily be demonstrated experimentally.’ 
In Fig. 6, suppose A and A’ to be both sinks (say two 
artesian wells) then the flow will be along the lines in the 
direction marked by the arrow heads. 
Fig. 7 illustrates the case of deflection of flow, initially 
in the direction D (see arrow), by the ‘sink’ or well W. 
The line BB is the dividing line on the left hand side, the 
flow going toward the well, on the right-hand side along 
the stratum. 
Imagine a stratum initially without flow in any direction, 
penetrated by two ‘sinks’ or wells, the efflux volume being 
twice as much in (2) as (1), see Fig. 8. The flow will then 
take place as indicated. i; 
Again if two equal ‘sinks’ or wells be put down intoa 
stratum with an initial flow in the direction D, the flow 
towards the wells will be as shewn in Fig. 9. 
These and similar cases have been solved,’ and throw 
light on the motion of water near wells, and on the reac- 
+ Kinfihrung in die Theorie der isogonalen Verwandschaften.— Gustav 
Holzmiiller, Leipzig, 1882. 
? See Engineering, April 8,15, 1898, pp. 444 — 477, ete. 
* By Professor Slichter and others. 
