N, September 12, inclose sketch of a
mounted man, whether on a horse or some other mammal, is a question
open to criticism.

[Illustration: Height, 43 in.; length, 63 in. San Rafiel del Sur, 1878
Drawn for and forwarded to Peabody Museum--No. 53.]

The figure seems incomplete--whether a cloven foot or toes were
intended, cannot say.

A large fossil horse was exhumed in the marsh north of Granada, when
ditching in 1863. Then Lake Managua's outlet at Fipitapa ceased its
usual supply of water to Lake Nicaragua. When notified of the
discovery the spot was under water. Only one of the very large teeth
was given to me, which was forwarded to Prof. Baird, of
Smithsonian--Private No. 34.

When Lake Nicaragua was an ocean inlet, its track extended to foot
hills northward. Its waterworn pebbles and small bowlders were
subsequently covered by lake deposit, during the time between the
inclosure and break out at San Carlos. In this deposit around the lake
(now dry) fossil bones occur--elephas, megatherium, horse, etc. The
large alluvium plains north of lake, cut through by rivers, allow
these bones to settle on their rocky beds. This deposit is of greater
depth in places west of lake.

Now, if we suppose these animals were exterminated in glacial times,
it remains for us to show when this was consummated.

Subsequent to the lake deposit and exposure no new proofs of its
continuance are found.

1. This deposit occurred after the coast range was elevated.

2. Elevation was caused by a volcanic ash eruption, 5 or 6 of a
series. (Geologically demonstrated in my letters to _Antiquarian_ and
_Science_.)

3. Coast hills inclosed sea sediment, now rock containing fossil
leaves.

4. Wash from this sediment, carried with care, formed layers of
sandstone, up to ceiling.

5. This ceiling was covered with elaborate inscriptions.

6. The inscription sent you was a near neighbor to cave.

7. Another representing a saurian reptile on large granite bowlder is
also a neighbor (a glacial dropping).

8. Old river emptying into Lake Managua reveals fossil bones; moraines
east of it are found.

From these data we see the glacial action was prior to the sedimentary
rock here, and had spent its force when elevation of coast range
occurred. No nearer estimate is possible.

As the fossil horse occurs here, our mounted man may have domesticated
him, and afterward slaughtered for food like the modern Frenchman.
Unfortunately Prof. Cope d