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found, and its rapid growth in height from its original dimensions is here 
noticed. Why should this have begun to form so recently, and have pro- 
gressed so rapidly, while weare asked to believe in the slow and uniform growth 
of all the rest of the stalagmite ? If we wanted a chronometer this Jockey’s 
Cap would be a very tempting one ; but why did it begin at so recent a period ? 
When you have a case in point such as this, a well-known case as to the 
measurement of stalagmite which began to grow without the smallest reason 
that can be alleged, it throws the very gravest doubt upon the whole question. 
The whole subject wants a great deal more examination than it has yet re- 
ceived before the science of the geologist can be regarded as certain. There 
is one thing that is certain in this controversy, and that is that we cannot 
calculate dates by any method which is at present in our possession. 
(Applause.) 
Mr. T. K. Callard. — I should like to give a case in point. Mr. Clark, 
writing to Nature, in December 1873, calls attention to some stalagmite 
forming on a gas-pipe. The fact he mentions is worth something because we 
know how long the gas-pipe has been there. This gas-pipe had been put 
down in Pool’s Cavern, near Buxton, about twelve years before Mr. Clark wrote 
his letter, and he says that on this pipe there was formed one-eiglith of an inch 
of stalagmite six months after the gas-pipe had been placed there. This, 
I think, is a good point. Now at this rate of formation the 12 feet of sta- 
lagmite for the deposit of which Mr. Pengelly has allowed 720,000 years could 
have been formed in 576 years. (Laughter.) There is another point in con- 
nection with the gas-pipe that goes to confirm the conclusions reached by 
Mr. Howard, and that is, that the accretion is not uniform. I have brought 
with me a boss which I had permission to take from the gas-pipe. This boss, 
I presume, is the same as was referred to by Mr. Clark, for no doubt he 
would have measured the largest, and this was the largest in the autumn of 
last year. That would make the period of formation seventeen years, as it was 
in 1873 that Mr. Clark wrote to Nature. When the boss w r as taken off the 
gas-pipe it measured one inch and three-sixteenths. What I wish to call 
attention to is the different rate of formation ; as at first, it was forming at such 
a rate that four years would have given an inch ; but subsequently the forma- 
tion so decreased that it would have taken more than fourteen years to form 
an inch. Consequently, this boss bears upon points that have been touched 
upon by Mr. Pengelly, and shows both the rapidity and the want of uniformity 
in the formation of stalagmitic matter. At the rate at which the formation 
commenced, when it was first noticed by Mr. Clark, it would, as I have 
stated, have taken 576 years to form a thickness of 12 feet, but at the rate at 
which it has been forming subsequently, it would take 2,061 years to make 
the same thickness, and both these figures are immensely different from those 
given by Mr. Pengelly, while they are sufficiently at variance with each other 
to prove the correctness of Mr. Howard’s position as to the non-uniformity 
of the accretion of stalagmite. 
The Chairman. — I think that those scientific men who are attempting to 
establish a law from what they assume to be a time rate, must be brought 
