of concavity; and this impression must remain, until the elevation shall bear so great a proportion to, the prospect, that the apparent parallelism of the base and hypothenuse, disappears.
The pigeons about this time seeming to undergo much suffering, I determined upon giving them their liberty. I first untied one of them, a beautiful gray-mottled pigeon, and placed him upon the rim of the wicker-work. He appeared extremely uneasy, looking anxiously around him, fluttering his wings, and making a loud cooing noise, but could not be persuaded to trust himself from the car. I took him up at last, and threw him to about half-a-dozen yards from the balloon. He made, however, no attempt to descend as I had expected, but struggled with great vehemence to get back, uttering at the same time very shrill and piercing cries. He at length succeeded in regaining his former station on the rim, but had hardly done so when his head dropped upon his breast, and he fell dead within the car. The other one did not prove so unfortunate. To prevent his following the example of his companion, and accomplishing a return, I threw him downwards with all my force, and was pleased to find him continue his descent, with great velocity, making use of his wings with ease, and in a perfectly natural manner. In a very short time he was out of sight, and I have no doubt he reached home in safety. Puss, who seemed in a great measure recovered from her illness, now made a hearty meal of the dead bird, and then went to sleep with much apparent satisfaction. Her kittens were quite lively, and so far evinced not the slightest sign of any uneasiness.
At a quarter-past eight, being able no longer to draw breath without the most intolerable paint, I proceeded, forthwith, to adjust around the car the apparatus belonging to the condenser. This apparatus will require some little explanation, and your Excellencies will please to bear in mind that my object, in the first place, was to surround myself and car entirely with a barricade against the highly rarefied atmosphere in which I was existing, with the intention of introducing within this barricade, by means of my condenser, a quantity of this same atmosphere sufficiently condensed for the purposes of respiration. With this object in view I had prepared a very strong, perfectly air-tight, but flexible gum-elastic bag. In this bag, which was of sufficient dimensions,
