972 PROCEEDINGS OF SECTION I. 
thickness. It is worthy of note that the clay referred to has a 
deteriorating effect on cast-iron pipes also, some of which having 
been in service for 20 years have been found so changed in 
character as to be incapable of withstanding even moderate 
pressures, the material being like plumbago instead of cast-iron, 
and as easily cut with a pen-knife as the black lead of a pencil. 
Its action on the coating of the steel pipes seems to be mechanical, 
but on the cast-iron chemical. In this connection I may say that 
we are now using galvanised-iron service piping everywhere with 
satisfactory results as to durability and economy. 
Recent experience in deep well boring operations is of special 
interest in relation to the question of the extent of the Central 
Australasian artesian basin. The rig known as the drop drill is 
that almost exclusively in use. The old cable drill was largely 
superseded some time ago by 2} inch steel-wire rope, and then 
the Canadian pole-drill was introduced and used very successfully 
in some classes of country (the diamond-drill being reserved for 
boring for minerals). I have found it most advantageous in the 
new rigs recently constructed to combine the pole and the steel 
rope so that either can be used as found desirable, and constructed 
so as to be capable of boring to 5,000 feet ; the result, undoubtedly, 
is the expediting and cheapening of the work. 
Tn this class of work the department provides the outfit and the 
casing, carries out all the carting, and lets contracts for labour 
only. There is no class of work in which we are engaged into 
which the element of chance seems to enter so largely—‘“ Bore 
out of perpendicular,” or ‘ Casing-shoe lost,” or “String of tools 
stuck at 2,000 feet,” are examples of the short but comprehensive 
telegrams often received following a carefully detailed report that 
all was going well, and the result of the work almost an assured 
success. All our casing is } inch thick, of BBB Staffordshire iron, 
with what is known as “swelled joint,” and varying in diameter 
from 12 inch to 5 inch, the largest size being always used to start 
with. 
Upon no subject have more erroneous notions been promulgated 
than in connection with deep well boring. The popular idea 
seems to be that a successful result in the obtaining of an artesian 
supply can be assured anywhere if only the bore is put down deep 
enough. 
That money has been wasted, through pressure brought to bear, 
in carrying out this idea is undoubted. In many instances we 
can only cover up the failure by saying that the bore was put 
down for experimental purposes, whereas if the voice of scientific 
reason had been listened to the money would have been saved, 
and the discredit avoided. It is still popular to reply, “ You did 
not go deep enough,” even to such a statement as this, and although 
the work may have ended in many feet of solid granite. 
