"A common paper kite containing 154 square inches was fastened to a rod of wood at the hinder end and supported from the fore part from the same rod by a peg, so as to make an angle of 6 degrees. With it this rod proceeded on behind the kite and supported a tail, made of two planes crossing each other at right angles, containing 20 square inches each. The tail could be set to any angle with the stick.

The ratio of about 5 square feet of surface to the pound - velocity 10 miles per hour. The centre of gravity was varied by sticking a weight with a sharp point into the stick. The whole weight [of the model] was 3.82 oz and the centre of gravity, G, was under such part of the kite as it left 75 square inches ahead of it and 79 square inches behind it, and with the tail at an angle of 11.5 degrees. The centre of the tail surfaces was 27 1/2 inches from the centre of gravity. 

If a velocity of 15 feet per second was given to it in a horizontal direction, it would skim for 20 or 30 yards supporting its weight. If pointed downwards at an angle of about 18 degrees, it would proceed uniformly in a right line for ever with a velocity of 15 feet per second. 

It was very pretty to see it sail down a steep hill, and it gave the idea that a larger instrument would be a better and a safer conveyance down the Alps than even the surefooted mule, let him meditate his track ever so intensely. The least inclination of the tail towards the right or left made its shape its course like a ship by the rudder."