DIRECTOR   Methodius Vann


Having lately proposed a plan for employing a balloon for an observatory, 1 shall now endeavor to describe more minutely the construction of a similar balloon, with apparatus for propelling and mode of managing the same under various circumstances, and show the comparative safely to which this mode of travelling may be reduced. A balloon 500 feet long and 50 in diameter, gradually tapering from the centre to a point at each end, (which figure, for want of a better name is called a pointed t:}>hi>. roid,) is made of strong sheeting, and is rcn. dered tight by oil or varnish ; and its form is supported by eight wooden rods, an inch and half in diameter, which extend the whole length of the balloon, inside of the sheeting, and are fastened together at the ends, but separate so as to be equidistant from each other towards the centre, the sheeting being nailed to the rods at every foot of their length, by which they are effectually kept in place. These rods, it will be understood, continue in contact the whole length, until the balloon is inflated, when they become separated as above mentioned. A stage fifty feet in length and twenty in breadth, constructed economically with re- gard to the weight of materials, is suspend- ed by cords about twenty feet below the bal- loon ; the cords, thirty or more in number, being attached to the stage at various points and convenient distances, are supported at the top by rings, which are attached by screws to the several rods or ribs of the bal- loon. The stage is further supported by four other cords, two ol which extend from the two forward corners of the stage to the forward point of the balloon, and the other two from the two hind corners to the steri point. T« this point is connected, by a uni versal joint, the end of a pole four inches in diameter, which extends backward hori- zontally twenty-five feet, tapering to the di- ameter of two inches. From the small end of this pole four arms project in opposite di rections ; and from the outward end of each arm, a cord extends to the forward end ofl the pole, being made fust to both. These arms are six feet long, ten inches wide, and one inch thick, being tmnoned to the pole, and supported by a wire which compasses the four, and is fastened to the end of each. To the space between each coitl and the pole, a piece of painted cloth is fitted, one edge of which is nailed to the pole, and the other is sewed to the cord : the wide end is also nailed to the arm. Other four arms, six feet in length, project in opposite direc- tions, two vertically and two horizontally, from the forward end of the pole, near the universal joint. Two cords extend from the small end of the pole to the ends of the two horizontal arms last mentioned ; thence forward to two pulleys, which arc attached to the sides of the balloon, a little forward of the centre ; thence down to a light steering wheel, on the forward part of the stage Three other cords proceed from the same point : two of which pass over the head oi the upper arms ; thence over two pullies near the first ; and the other cord passes to the end of the lower arm, thence over a pu ley attached to the lower side of the balloon ; and the three terminate on a small shaft with a crank, ratchet and fall, near the steer- Ding wheel, that the steersman may be able to govern the vertical as well as horizontal variations in the direction of the balloon.