456 T'ransactions, —Chemistry. 
cent. of nickel is mined with profit ; while at Frieberg, in Saxony, even a 
much lower percentage is thought well worth the expense of recovery. 
I cannot allow this short note to close without a few words upon a metal 
frequenily aecompanying nickel: I allude to cobalt. In the instances 
which I have already mentioned I did not find a trace of this metal, though 
I have succeeded in discovering it in this district in four distinct places in 
the shape of asbolite, the highest percentage yet found being 9-49 per cent., 
and this entirely free from nickel. I hope in the coming summer to still 
further investigate these deposits and bring the matter again before the 
Institute. With respect to the successful manipulation and refining of 
these minerals for commercial purposes in New Zealand, I am afraid very 
little can be done until we have sulphurie acid manufactured in the colony, 
as the importation of this article entirely excludes all chances of successful 
competition with the home refiners, and in consequence ores which might 
be utilized with profit must lie idly by awaiting the time when, from the 
cheap production of acid and its concomitant products, there may be a 
possibility of extending our manufaetures and utilizing some of the raw 
material which the colony possesses. 
Arr. LXX.—Notes on a Deposit in the Shaft of the Pumping Association. 
By G. Brack. — i 
[Read before the Auckland Institute, 90th August, 1877.] 
I zxmrmerr samples of the lime deposit which lately formed in the pumps 
and upon the timbers of the United Pumping Association shaft; the slab 
was broken off one of the timber frames in the shaft at a depth of 540 feet 
from the surface. I will briefly give a few details of its mode of occurrence. 
; This incrustation was first observed when the shaft was about 530 feet 
deep; in sinking at that depth a large body of quartz had been cut through, 
and when the strata upon which the quartz was lying was cut into, a great 
change took place; the water formerly was acidulous, it now became 
alkaline, and it was highly charged with carbonate of lime, which it held in 
solution and precipitated as it came in contact with the carbonic acid gas in 
the shaft. This deposit formed remarkably fast, and did not continue 
regular, some weeks it would form more in thickness than it did in others. 
The average thickness it formed on the buckets of the pumps was about a 
quarter of an inch in a week; it would coat a pick handle or drill in twelve 
hours, and this was a great source of annoyance to the men working in 
the bottom of the shaft, as the pick and hammer handles got coated with 
