text:  And yet it was not till this comparatively advanced stage of the nautical art--when man had obtained a faithful guide in his most devious and trackless wanderings--when he was apparently set free from the unsteady dominion of the seas and of the fickle winds--and amid his labyrinthine course could ever and at once turn his face towards his happy and expectant home;--it was not till this period that science began to lend her most useful and most extensive aids and that her value in the advancement of the sailor's art began to be justly appreciated