Capt. Hall on a Bridge of Suspension made of Hide-Ropes. 53 
I was informed on the spot, that these South American 
bridges were found, exactly as they now exist, by the Spaniards, 
when they first occupied the country three centuries ago ; and 
it is quite as certain, that nothing was known of this principle, 
as applied to iron, till within these few years. 
I have not heard whether Captain Brown, the well-known 
inventor of the Chain-Cable, and who first introduced the iron- 
bridge of suspension, claims it as an original invention. His 
merit, however, is not, as I conceive, in the smallest degree 
lessened, by supposing him to have seen or heard of these hide- 
bridges of South America ; for it is quite as praiseworthy an 
exercise of genius and talents to observe and turn to account 
such analogies as these, as it is to invent what is altogether 
new. Indeed, this is one of the broadest distinctions, by which 
the mere visionary theorist is separated from the useful, prac- 
tical adapter of known and tried principles to the business of life. 
It is, however, a curious subject of scientific history, to trace 
the progress of such inventions and adaptations, from their 
rudest to their most perfect state ; and I shall be very happy 
if this notice shall have the effect of inducing the ingenious 
and able officer alluded to, to favour the public with such an 
account, not only of this invention, but also that of the chain- 
cable, which, as a seaman, I may be excused in describing as one 
of the most important applications of principles with which every 
person was familiar, but no one turned to account, till the saga- 
city and perseverance of Captain Brown taught us their use. 
Addition by the Editor . 
In an interesting Report by Captain Brown, “ on the proposed 
plan of erecting a Patent Wrought-Iron Bridge of Suspension 
over the Thames, near Iron-Gate and Horslydown,” which we 
hope to lay before our readers in the present or next Number 
of this Journal, the following remarks occur, which bear on the 
subject of Captain Hall’s account of the Native American 
Bridge. 
<c It will not at all lessen the importance of the present pro- 
posal, if it be admitted that bridges of suspension have long ex- 
isted in other countries, and it cannot be pretended by any man 
that a new principle has been discovered. The properties of 
the catenarian curve are obvious in the Indian bridge of suspem 
