est 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
me might be adapted equally to any of the window lenses, and throw a
perfect image, magnified by 100, 1000, or 5000, upon mirrors properly
placed.

I carpeted the floor with several alternate layers of cork and cloth.
At one end I placed my couch, table, bookshelves, and other necessary
furniture, with all the stores needed for my voyage, and with a
further weight sufficient to preserve equilibrium. At the other I made
a garden with soil three feet deep and five feet in width, divided
into two parts so as to permit access to the windows. I filled each
garden closely with shrubs and flowering plants of the greatest
possible variety, partly to absorb animal waste, partly in the hope of
naturalising them elsewhere. Covering both with wire netting extending
from the roof to the floor, I filled the cages thus formed with a
variety of birds. In the centre of the vessel was the machinery,
occupying altogether a space of about thirty feet by