* * * * *

Briefly, having determined to take advantage of the approaching
opposition of Mars in MDCCCXX ... [3], I had my vessel constructed with
walls three feet thick, of which the outer six and the inner three
inches were formed of the metalloid. In shape my Astronaut somewhat
resembled the form of an antique Dutch East-Indiaman, being widest and
longest in a plane equidistant from floor and ceiling, the sides and
ends sloping outwards from the floor and again inwards towards the
roof. The deck and keel, however, were absolutely flat, and each one
hundred feet in length and fifty in breadth, the height of the vessel
being about twenty feet. In the centre of the floor and in that of the
roof respectively I placed a large lens of crystal, intended to act as
a window in the first instance, the lower to admit the rays of the
Sun, while through the upper I should discern the star towards which I
was steering. The floor, being much heavier than the rest of the
vessel, would naturally be turned downwards; that is, during the
greater part of the voyage towards the Sun. I placed a similar lens in
the centre of each of the four sides, with two plane windows of the
same material, one in the upper, the other in the lower half of the
wall, to enable me to discern any object in whatever direction. The
crystal in question consisted of ..., which, as those who manufactured
it for me are aware, admits of being cast with a perfection and
equality of structure throughout unattainable with ordinary glass, and
wrought to a certainty and accuracy of curvature which the most
patient and laborious polishing can hardly give to the lenses even of
moderate-sized telescopes, whether made of glass or metal, and is
singularly impervious to heat. I had so calculated the curvature that
several eye-pieces of different magnifying powers which I carried with