Walker, Ralph <br/><br/>
A  Treatise on the magnet, or  natural lodestone, with tables of the variation of the magnetic needle, for all latitudes and longitudes, observed at different times in the Atlantic, Indian, and Pacific Oceans, by the following celebrated navigators  ... together with tables of the dip of the globe, and a description of a new-invented meridional and azimuth compass. Illustrated with seven folio plates. To which is added, an appendix, containing hints to ship builders and navigators 

 - London :  Printed for M. Allen...and T. Wallis...,  1798. 
 - 1p.1., [5]-226p. :  VII plates tables 
<br/><br/> Tables edition is the same as that of 1794 except for the change of title. 
<br/><br/><label>Dewey Class. No.: </label>538 Ja W183