Page:Miscellaneous Papers on Mechanical Subjects.djvu/169

 railroad cars or carriages commonly used in the United States has been frequently described.

They are very long, and are supported at each end on four-wheeled trucks, on which they swivel when turning the sharp curves, which are of ordinary occurrence.

A car constructed for sixty passengers measured 40 feet long, 8½ feet wide, and 6½ feet high, inside measure; small benches with reversible backs, having each two seats, are ranged parallel to each other down both sides of the carriage, leaving a passage clear from the door at one end to that of the other. The car afforded upwards of 2,200 cubic feet of space, or 37 feet per passenger. Its weight was 11 tons, giving a dead weight of about 3½ cwt. per passenger.

The cost of a 60-passenger car is about $2,000 (400l.).

A contrivance has been lately tried for excluding the dust by connecting the different carriages together by indiarubber curtains at the ends, the air being admitted through the roof of the first carriage.

The object sought to be obtained is, a current of air running through the entire train, and always setting outwards from the interior of the carriages. The results did not appear to answer fully the expectation which had been formed