58 ANNUAL OF SCIENTIFIC DISCOVERY. 



noise from the outside being obliged to enter the car against the strong 

 current of air passing out of the windows. 



There are also two objections to this system of ventilation. The 

 first is that when the car is not moving, (for instance in the station- 

 house,) the passengers will be in danger of becoming stifled, since the 

 rapid motion of the car is necessary in order to force any considerable 

 quantity of air into the car through the ventilators. 



The other objection is, that in cold weather the new apparatus will 

 force too much cold air down upon the heads of passengers ; and that 

 the open windows, which form an essential part of the plan, will then 

 be found disagreeable. 



The New Haven Courier gives the following description of another 

 invention designed to promote the comfort of passengers travelling by 

 railroad : " The invention consists merely in a connection formed 



/ 



between all the cars by inclosing the platforms, so that the external 

 air, with the dust, smoke and cinders, are entirely excluded from the 

 usual ways of ingress. The front of the baggage car is open, but pro- 

 tected from the smoke of the locomotive by a screen. The air rushes 

 in through the front of the car, and circulates freely through the whole 

 length of the train, keeping up at all times a gentle motion of the 

 air, without the possibility of annoyance from dust, &c. It has its 

 advantage over Mr. Paine's ventilator, that when the air is at rest, 

 the passengers have the free use of the ordinary means of ventila- 

 tion by doors and windows, and thus the intolerable heat is avoided, 

 while there is no fear of the admission of smoke, which forces itself 

 into Paine's ventilators when passing under bridges, or on a wet day, 

 when the wind is dead ahead, and rolls it along the roof." 



At the Fair of the American Institute in October, 1852, at New 

 York, some twenty-five different models of improvements for ventila- 

 ting cars were on exhibition. The two of most apparent importance, 

 were those mentioned above. Editor. 



RAILWAY IMPROVEMENTS. 



Trink's Doitlle Acting Brake. The principle of this is to raise 

 the wheels off the track in this manner : The brake, which is made of 

 transverse pieces of wood, forming a frame, is placed behind the 

 wheels, and is connected by a rope or chain with the screw or lever 

 on the platform of the car, by which the brake or frame can be drop- 

 ped or raised instantly. On this frame or brake are inclined planes 

 forming part of a circle, and when the frame is dropped for the pur- 

 pose of stopping the train, the momentum of the train causes the cars 

 to run on the axles of the wheels up the inclined plane, thus lifting 

 the wheels off the rails and throwing the weight of the cars on the 

 frame, pressing it on the rails, and acting as a brake. The frame 

 when down, rests upon iron shoes, three upon each side, which are 

 prevented from sliding off the rails by means of flanges on the inside, 

 similar to those on car Avheels. The brake thus unites two capacities : 

 First, in raising the cars, by which operation, although the wheels 



