G. H. KNIBBS. i, RXLX, 
Professor Gregory combats the conventional view (a) 
that the artesian source is the water under hydrostatic 
(or hydraulic?) pressure in a porous bed interstratified 
between two (relatively ?) impermeable beds. He says (b) 
** But in nature artesian wells occur where there are no 
tubular spaces, and where the water works its way along 
minute crevices and capillary pores,” that (c) ‘‘ under such 
conditions the pressure of water in the higher part of the 
bed is soon sopped up by the friction against the sides of 
the channels,”’ (d) “‘ and that the hydrostatic head is lost 
long before we reach the bore.’”’ He says, further (e) 
**Artesian flow is in most cases due to the earth’s internal 
heat.”’ After pointing out that at a depth of 8,250 feet (?) 
the water would reach 100° C., but cannot boil on account 
of pressure, he says (f) ‘“‘ If the pressure be relieved then 
the water bursts into steam, . . or it would allow the 
expansion of the water and the contained gases.” . . (g) 
‘‘ The artesian bore through the upper impermeable strata 
relieves the pressure . . and accordingly its expansive 
forces and imprisoned gases compel it to rise to the sur- 
face.’” 
Professor Gregory’s view is, we venture to think, unten- 
able for the following reasons :— 
(a) The only necessary assumption is relative imperme- 
ability of the overlying strata. 
(b) In some artesian wells, in the Sahara for instance, 
there is biological evidence of fissures occurring: 1.e., 
artesian water may come from either porous beds, or beds 
in which there are channels of various sizes. 
(c) Hydrostatic pressure never disappears by friction, 
though its effect may sometimes be masked by surface- 
tension. 
+ Dr. J. W. Gregory, Professor of Geology and Mineralogy, University 
of Melbourne.—Australian Mining Standard, xx., 26 Dec., 1901, pp. 1002-3. 
