CHAPTER XXII.

BALLOON AT ITS GREATEST HEIGHT.

[Sidenote: Mouth of the Balloon opened.]

Section 122. Being cautious how he suffered the +lightest+ Gass to escape throu’ the Top of the Balloon, which must have happened in drawing down the String of the Valve; yet apprehending the +Possibility+ of an immediate Rupture at its +present greatest+ Elevation;—glancing his Eyes _around_ to take a +farewel+ View;—he _pulled_ the Twine, that tyed the +Neck+.

[Sidenote: Balloon _shrunk_ to its usual _Shape_.]

123. _Instant_ Relief was given to the Balloon: which shrunk into the Shape which it had assumed in the former Ascent, when the Gass began to issue in visible Vapour, the _Neck_ likewise _lowering_ itself to the Height of his Shoulders, as in Section 35.

[Sidenote: Mouth _opened_ at 41 Minutes past III.]

124. On stooping he found the Time 41 Minutes after III, and the Thermometer 57.

[Sidenote: No _visible_ Vapour escaped.]

Nor was he surprised that no _visible_ Vapour escaped; as he had imagined that much _common_ Air had been pressed into the _Mouth_ of the Balloon: and which, being _heavier_ than Gass, woud _go out first_.

[Sidenote: Why the _Valve_ at the Top is not to be _opened_.]

On that Ground he was confirmed in his Resolution _not_ to open the Valve at the top, which always emits the _lightest_ Gass.

[Sidenote: The _Neck_ being made _Air-tight_, the Balloon rose _again_.]

125. As soon however as the Neck of the Balloon reached his Shoulder, he _gathered_ the Silk in his Hand, and held it _Air-tight_ tho’ untyed, to prevent Evaporation of much _real_ Gass: presuming that if any Levity remained; the Balloon woud presently _rise_ again, and _swell_.

And he was pleased to find the Event answer his Expectations.