My dear old W.

I have carefully washed & examined the 4 castings from Brading & they have yielded a large number of bits of tiles or bricks, which are more or less rounded, & a multitude of bits of mortar & white calc. cement.—² But it is extremely difficult to judge whether the rounding is due to the action of the gizzards of worms.— I am very much obliged for the great trouble which you took about the Brading ruins & I am very glad to have your account.³ Everything agrees pretty closely with what I have seen or heard elsewhere.— It is odd some of the floors having subsided in the line of slope of the field.—

There are 2 questions, which you may perhaps be able to answer: are the ruins in the upper or lower part of the field which slopes at about 3°; for if in the lower part much earth will have been washed down.

Secondly can you remember whether the floor of the great room (40 ft x 18 ft) whence you got the castings, lay at some considerable depth beneath the surface of the field.—

I return slip to avoid chance of loss.

Judging from letters from Germany the “Power of Movement” will prove a good hit in Phys. Botany. There is no one in this country who knows anything of the subject.—⁴

It will be very nice seeing you & Sara here so soon.—⁵

When you have any leisure (if such time ever comes) try & make out relation of the brick earth near you to the angular gravel-bed.

Ever yours affect | C. Darwin