In the meantime Barbicane was making his arrangements in the projectile as though he was never going to leave it.  It will be remembered that the base of the aerial vehicle was fifty-four feet square.  It was twelve feet high, and admirably fitted up in the interior.  It was not much encumbered by the instruments and travelling utensils, which were all in special places, and it left some liberty of movement to its three inhabitants.  The thick glass let into a part of the floor could bear considerable weight with impunity.  Barbicane and his companions walked upon it as well as upon a solid floor; but the sun, which struck it directly with its rays, lighting the interior of the projectile from below, produced singular effects of light.

They began by examining the state of the water and provision receptacles.  They were not in the least damaged, thanks to the precautions taken to deaden the shock.  The provisions were abundant, and sufficient for one year’s food.  Barbicane took this precaution in case the projectile should arrive upon an absolutely barren part of the moon.  There was only enough water and brandy for two months.  But according to the latest observations of astronomers, the moon had a dense low and thick atmosphere, at least in its deepest valleys, and there streams and watercourses could not fail.  Therefore the adventurous explorers would not suffer from hunger or thirst during the journey, and the first year of their installation upon the lunar continent.

The question of air in the interior of the projectile also offered all security.  The Reiset and Regnault apparatus, destined to produce oxygen, was furnished with enough chlorate of potash for two months.  It necessarily consumed a large quantity of gas, for it was obliged to keep the productive matter up to 100 deg..  But there was abundance of that also.  The apparatus wanted little looking after.  It worked automatically.  At that high temperature the chlorate of potash changed into chlorine of potassium, and gave out all the oxygen it contained.  The eighteen pounds of chlorate of potash gave out the seven pounds of oxygen necessary for the daily consumption of the three travellers.

But it was not enough to renew the oxygen consumed; the carbonic acid gas produced by expiration must also be absorbed.  Now for the last twelve hours the atmosphere of the bullet had become loaded with this deleterious gas, the product of the combustion of the elements of blood by the oxygen taken into the lungs.  Nicholl perceived this state of the air by seeing Diana palpitate painfully.  In fact, carbonic acid gas—­through a phenomenon identical with the one to be noticed in the famous Dog’s Grotto—­accumulated at the bottom of the projectile by reason of its weight.  Poor Diana, whose head was low down, therefore necessarily suffered from it before her masters.  But Captain Nicholl made haste to remedy this state of things.  He placed on the floor of the projectile several receptacles containing caustic potash which he shook about for some time, and this matter, which is very greedy of carbonic acid, completely absorbed it, and thus purified the interior air.