PART 1.] 
Medlicotf ■ Wells at Ilazareehagh. 
17 
direction the ridges are confluent. The site for the Central Jail is some few score yards be¬ 
yond the Penitentiary, on another minor branch of the same system of ridges. In both 
localities rock crops out freely in many places, and it might have been anticipated from the 
beginning that the well question would assume a very different aspect from that of any case 
within local experience. It were useless to moralise upon so common an occurrence as want 
of foresight, or to indicate its source in this particular instance. 
10. In the Penitentiary well there is no clay at top. After about 3 feet of coarse 
quartz gravel, mixed with red sandy earth, they come upon a run of largely crystallized 
granite (pegmatite) very irregularly associated with hornblendic gneiss. At first this mass 
was not difficult to be cut, although not nearly so soft as the rotten rock already spoken of, but it 
rapidly became harder, and at about 20 feet blasting had to be resorted to. All effects of 
decomposition from surface atmospheric influence having ceased, the. stone showed its true 
characters of intense hardness and complete impermeability. The arrangement of the 
bedding, if, indeed, it be true bedding, in this short shaft is exceedingly irregular, at one 
spot apparently dipping to the north, and at another to the west. In the hard rock at base 
there are some well marked joint planes showing large flat surfaces nearly vertical, but these 
joints do not seem to be available for the percolation of water; the few leakages that occur 
are from points in the indefinite cracks that traverse the stone discontinuonsly without any 
system, and generally where there is a film or layer of partially disintegrated rock. Near 
the base of the shaft another vein of granite like that at top, but thinner, traverses the 
gneiss irregularly at a low average angle, but here it is firmly i lited with the containing 
rock, the same even surface of fracture passing indiscriminately through both. I waited for 
several days to have this well emptied, but the water was still knee-deep at my last examina¬ 
tion. I do not consider that I have lost any evidence of importance. 
11. From the accounts I have received, there would seem to be some prospect of 
immediate success. I am informed by Dr. Coates that a few days before the work closed at 
the end of the hot season, he made a rough measurement of the leakage water, and found 
it to be about 40 gallons per hour, nearly 1,000 per day. I confess that this surprises me 
much : the excavation then w r as at about the level the water stood at when I saw it last, and 
the leakage did not seem to me any thing like so much, although the time of year was so 
much more favorable, and the well had just been emptied by double gangs of men working 
day and night. Subsequent to that measurement, the last few blasts put into the rock 
disclosed one or more layers much softer than any met with for some yards above, and from 
which water flowed in much greater abundance than from any of the higher points. Unfor¬ 
tunately the rains put a stop to the work before this ground could be fully proved. The only 
symptoms I could detect of these sources was that, in walking about through the water, 
I felt at two or three spots a very appreciable warmth under my feet. The first thing to lie 
done now is fully to test this ground. Five or 6 feet mere of cutting ought to prove what 
it is worth. But a large margin ought to be left above any measurement made now for the 
diminution that may be expected in the dry season. 
12. There can, of course, be no doubt of ultimate success; accumulated drippings will 
at last yield the required supply. But this must remain matter of experiment. No one 
but a diviner would venture to predict at what point success would be attained in rocks like 
these. There is, however, an evident choice as to the direction in which these contributions are 
to be sought. That word “ spring” has a great deal to answer for: most men seem to think 
that water comes from the bowels of the earth, whereas in 99 out of 100 apparent cases 
the source is from above. The only available, and the only known, source of water here is 
the one already pointed out, the porous mass of disintegrated rock at the out-crop under 
the clay. This being the case, I would decidedly recommend, in the event of the next few 
feet in depth not giving the required supply, that the vertical shaft be changed for a nearly 
horizontal drift. The chances are almost all in favor of this plan, and there is here the 
ultimate certainty of tapping the source itself in the most effectual manner from below. 
In the vertical shaft there is no doubt the chance of contributions from every side, while in 
the drift we must select the most likely direction, but I am in favor of this attempt. There 
are two elements for consideration, the structure of the rocks, and the lie of the surface. 
From what has been seen of the rocks in the Penitentiary well, there is little or no room 
for choice; they have no definite arrangement. The most frequent run of the rocks in this 
neighbourhood is about north-north-west* and so the most likely line to cut them would be 
at right angles to that direction. The primd facie view of the second condition would 
c 
