382 Correspondence—Mr. H. H. Howorth. 
forms pools on loam enters into Loess as into a sponge, and perco- 
lates it without in the least converting it into a pulp or mud.” 
This at once answers Mr. Wood’s notion, that when the ground 
is frozen to great depths the surface layers of Loess, when melted 
by the summer sun, would be converted into sludge. And this is 
essential to his theory; for, as he says, where the material acted on 
is porous sand or gravel, the water arising from the summer melting 
of the surface layers would escape laterally without any displace- 
ment of the material itself. This is exactly the case with Loess, 
which is more porous than sand or gravel. 
Again, how can Mr. Wood invoke the severely Arctic conditions 
his theory necessitates when he examines the Mammals, the Molluscs, 
and the Plants whose remains are found so widely distributed in 
the Loess? They bespeak comparatively temperate conditions when 
the Loess was deposited. Lastly, granting that these fundamental 
difficulties were overcome, it is assuredly unsafe to base such an 
induction as Mr. Wood makes upon a series of hypothetical data, as 
to the action of frost upon beds of soft material without, so far as 
I know, a single empirical test. We may as well claim the mirage 
for reality. Is not his method the very one he reprobates in the 
sentence about resorting to causes wholly supposititious, or only 
found to be in action to some very subordinate extent? It is in the 
domain of logic and geological induction, where we are equal, and 
not of geological observation, where we are not, that I claim to meet 
Mr. Wood, and to show that his arguments as applied to the real 
Loess, and not to some hypothetical Loess, are incomprehensible. 
I must, in conclusion, reply to my old friend Professor Dawkins. 
I am not going to discuss with him whether there be a special logic 
for Lawyers, and another for Professors, nor whether in the terribly 
wide inductions that Science must make nowadays, if it is to compass 
all the facts, it is prudent or wise to base arguments on our own 
observations only, or on the observations of all good men. These 
are matters upon which your readers will, I am sure, not agree with 
Mr. Dawkins. Let us turn from such small issues to one of real 
importance, namely, the range in time of the Mammoth. Professor 
Dawkins admits that I was right in saying he had changed his view — 
on this subject. He claims to have done so because of fresh evidence. 
First he cites the Scotch caves. This reference is a mystery to 
me. I know of no Scotch caves containing Mammoth remains, and 
I should be obliged by a reference to them. Secondly, he refers to 
Dr. Falconer’s opinion, but Dr. Falconer’s opinion was before him 
when in 1869 he wrote as follows of the Pre-Glacial Mammals: 
“To this list Dr. Falconer would add the Mammoth; but a careful 
investigation into the evidence which was supposed to establish its 
Pre-Glacial age has convinced me that the inference was faulty. 
The specimens reported to come from the ‘ Forest Bed’ are in every 
case mere waifs and strays thrown up by the sea between high- and 
low-water mark, or very possibly derived from the sands above the 
Boulder-clay. The remains dredged up from the bed of the sea, in 
the collection of Mr. Owles, establish the fact that a Post-glacial 
