If you would be otherwise, DARE _to be ignorant_ of all books, and all things, which you are not sure will repay your trouble in reading them, or which are not parts of a pre-arranged course, laid down for you by yourself, or by some judicious friend. DARE to disavow an acquaintance with a fashionable novel, or even with a fashionable science, if it fall not within your plan. Always reflect, when the claims of a new book are pressed upon your notice,--that, _if you have forty years to employ in reading, and can read fifty pages a day, you will be able, in those forty years, to accomplish only about_ SIXTEEN HUNDRED VOLUMES, _of 500 pages each_. Yes--out of the millions of tomes that litter the world, you can read, in twice the time that most, even of the studious, employ in reading--only sixteen hundred volumes! Surely, the motto of every one who reads for improvement, ought to be "SELECT WELL!" "It is a great, nay the _greatest_ part of wisdom," says an old philosopher, "to rest content with not knowing some things."[1] [Footnote 1: ----"magna, immo, maxima, pars sapientiæ est, quædam æquo animo nescire velle."] Dugald Stewart justly observes, that by confining our ambition to pursue the truth with modesty and candor, and learning to value our acquisitions only so far as they contribute to make us wiser and happier, we may perhaps be obliged to sacrifice the temporary admiration of the common dispensers of literary fame; but, we may rest assured, it is thus only we can hope to make real progress in knowledge, or to enrich the world with useful inventions. "'It requires courage indeed' (as Helvetius has remarked,) 'to remain ignorant of those useless subjects which are generally valued:' but it is a courage necessary to men who either love the truth, or aspire to establish a permanent reputation."[2] [Footnote 2: Philosophy of the Human Mind, Vol. I.] SKETCHES OF THE HISTORY AND PRESENT CONDITION OF TRIPOLI, WITH SOME ACCOUNTS OF THE OTHER BARBARY STATES. NO. X.--(Continued.)