To W. B. D. Mantell   10 April [1856]¹

My dear Sir

I am very much obliged to for finding time, amidst all your avocations, to answer my questions so fully.—

With regard to the erratic blocks, the most suspicious circumstance in regard to their truly erratic character, is, as it strikes me, their all consisting of the quartz rock.— Generally, but certainly not always, one finds several kinds of rock; nor do I quite understand that you are sure that they are separate fragments, & not rock in situ peeping out. Did M^r Harris refer to them as loose or separate blocks?² if so I sh^d. think the evidence was in favour of their belonging to the so-called erratic class.—³

Perhaps when you send me the iceberg sketch, you will answer this about M^r. Harris.—

If I have not utterly exhausted your patience, I sh^d be particularly obliged if you would inform me whether you think the evidence is really good that there formerly existed some animal (with hair?) like an otter or Beaver: I am much surprised at this. Could it not have been any water bird or reptile?⁴

Lastly, I fear you cannot answer my question whether the beau ideal of beauty amongst the less civilised natives (ie those least influenced by being accustomed to European faces) would agree with ours; viz whether we & they would pick out the same kind of beauty.—⁵ Forgive me if you can, & believe me,

Your’s truly obliged | Charles Darwin