Having a pretty large corner of the Plate for the seven Starrs, void, for the filling it up, I have added one small Specimen of the appearance of the parts of the Moon, by describing a small spot of it, which, though taken notice of, both by the Excellent Hevelius, and called Mons Olympus (though I think somewhat improperly, being rather a vale) and represented by the Figure X. of the 38. Scheme, and also by the Learn’d Ricciolus, who calls it Hipparchus, and describes it by the Figure Y, yet how far short both of them come of the truth, may be somewhat perceiv’d by the draught, which I have here added of it, in the Figure Z, (which I drew by a thirty foot Glass, in October 1664. just before the Moon was half inlightned) but much better by the Reader’s diligently observing it himself, at a convenient time, with a Glass of that length, and much better yet with one of threescore foot long, for through these it appears a very spacious Vale, incompassed with a ridge of Hills, not very high in comparison of many other in the Moon, nor yet very steep.  The Vale it self ABCD, is much of the figure of a Pear, and from several appearances of it, seems to be some very fruitful place, that is, to have its surface all covered over with some kinds of vegetable substances; for in all positions of the light on it, it seems to give a much fainter reflection then the more barren tops of the incompassing Hills, and those a much fainter then divers other cragged, chalky, or rocky Mountains of the Moon.  So that I am not unapt to think, that the Vale may have Vegetables analogus to our Grass, Shrubs, and Trees; and most of these incompassing Hills may be covered with so thin a vegetable Coat, as we may observe the Hills with us to be, such as the short Sheep pasture which covers the Hills of Salisbury Plains.

Up and down in several parts of this place here describ’d (as there are multitudes in other places all over the surface of the Moon) may be perceived several kinds of pits, which are shap’d almost like a dish, some bigger, some less, some shallower, some deeper, that is, they seem to be a hollow Hemisphere, incompassed with a round rising bank, as if the substance in the middle had been digg’d up, and thrown on either side.  These seem to me to have been the effects of some motions within the body of the Moon, analogus to our Earthquakes, by the eruption of which, as it has thrown up a brim, or ridge, round about, higher then the Ambient surface of the Moon, so has it left a hole, or depression, in the middle, proportionably lower; divers places resembling some of these, I have observ’d here in England, on the tops of some Hills, which might have been caus’d by some Earthquake in the younger dayes of the world.  But that which does most incline me to this belief, is, first, the generality and diversity of the Magnitude of these pits all over the body of the Moon.  Next, the two experimental wayes, by which I have made a representation of them.