926 Traksactiqxs of tbe American Institute. 



much to expect that this enterprise will be duly appreciated and in 

 time rewarded. 



In the construction of tliis great working model, there are some 

 peculiar features which will call for explanation as we proceed in the 

 description of the construction as a whole. Beside the great tube for 

 experimental passenger conveyance, there is a full sized model of a 

 pneumatic dispatch with noticeable improvements, which we shall 

 also have to notice in this article. 



The tube of the passenger railway at the fair was suspended 

 along the eastern wall and from gallery to gallery, a distance of 

 107 feet. It is six feet in diameter and is constructed of wood. 

 The shell is but one and a half inch thick, yet it is claimed to be 

 capable of immense resistance. This peculiarity is obtained by a 

 novel process patented some time since by J. K. Mayo. The inch 

 and a half in thickness is made up of fifteen layers or lamina of 

 veneer, laid upon each other transversely and spirally and joined 

 together by cement. The grain of the woods tlius crossed and 

 recrossed, gives a structure of remarkable strength and power of 

 resistance to either blow or pressure. The carriage for passenger 

 conveyance is long enough to seat on either side, iike the ordinary 

 street car, ten persons. It is open at the top and sides, the latter 

 rising sufficiently high only to protect the passengers' backs from 

 friction against the sides of the tube. The door is placed in the 

 center of the O shaped end which forms the valve or piston when 

 the door is closed. The wheels of the car, four in number, rest on 

 rails laid along the bottom of the tube and project through the bot- 

 tom a few inches only, being all that is necessary. The wheel 

 attachments and, with this exception, the wheels themselves are 

 immediately beneath the seats. This permits full use of the space 

 within the tube, so that the carriage is just as freed from touching 

 the bottom as the sides. The motive power, placed at the northern 

 end of the tube, consists of a great fan ten feet in diameter, inclosed 

 in a wooden cliamber which forms one end of the tube. This fan is 

 unlike any yet used. It is in fact a screw propeller with eight blades, 

 so Constructed that the pitch of the blades is not more than twelve 

 inches. This fan is driven by an engine placed near by, and will 

 make, if necessary, two hundred revolutions per minute. Turning 

 in one direction it produces a vacuum by exJiausting the air from the 

 tube and throwing it off through apertures in the chamber, thus 

 drawing the car at the other end rapidly toward it. When its motion 



