Transcriber's notes
Only obvious printer's errors have been corrected (e.g.: 3 s instead of 2, etc.). The author's spelling has been maintained and inconsistencies have not been standardised.
The advertisement pages have been move from the front to the end of the book.
Other corrections made:
—Page [x]: "the wealth of rations" has been replaced by "the wealth of nations".
—Page [17]: "Pressure of Rarified Air." has been replaced by "Pressure of Rarefied Air."
—Page [98]: "This beautiful contrivance, which is incontestibly" has been replaced by "This beautiful contrivance, which is incontestably".
—Page [100]: "the working beam no longer used" has been replaced by "the working beam is no longer used".
—Page [223]: "is attended with peliar difficulty" has been replaced by "is attended with peculiar difficulty".
—Page [271]: "The projecter is now employed in" has been replaced by "The projector is now employed in".