The First number of the Ninth Volume of the SCIENTIFIC AMEKICAN will be issued on the 17th of September, We are grateful for the very liberal encouragement which wehave received from our readers, and take this occasion to express to them our gratitude. We are also under many obligations to our cotemporariea for favorable notices. The next volume will be commenced with neiv and beautiful type, printed on paper manufactured expressly for this publication, of greatly increased weight and finer quality : this item alone will increase our yearly expenses over $3000 j in addition to this we shall increase our present able Editorial force as it is our intention to continue the Scientific Americans " THE LEADING AND MOST RELIABLE PRACTICAL SCIENTIFIC JOURNAL IN THE UNITED STATES." It will continue the unflinching advocate of all useful improvements, and it will fearlessly expose all unreliable and deceptive schemes appertaining to its character; Lin this respect it has gained a reputation superior to any other work of the kind in the world] The opening of the CRYSTAL PALACE in this city forms an object of rare public interest; we shall devote a full page of tlie paper every week to careful criticisms, reviews, aid illustrations of the objects most worthy of attention. We hope to render this department especially interesting to all our readers, whether they visit the Pair or not. The copious and FINELY EXECUTED ENGRAVINGS of Machinery, New Inventions, etc.—the TOUR HUNDRED PAGE3 of valuable Scientific and Practical Reading—the USEFUL RECEIPTS—the full Be-yortloi all the PATENT CLAIMS, and the relia bi** .ura.i'.tflr of the journal on all branches within its field of labor—render it worthy of the support which it has so liberally received from its intelligent class of readers. The circulation of the Scientific- American during the present volume has exceeded EIGHTEEN THOUSAND COPIES PEB WEEK. The edition on the new volume will be commenced 4ith twenty-three thousand, fwhich we feel confident will not be an over calculation. Subscribers, to ensure the numbers from the commencement of the volume, should Eend in their subscriptions early, as many were disappointed in not obtaining the complete eet of the present volume. The Scientific American is in form SUITABLE OK BINDIND, and each volume is accompanied with a full Index of all the subjects, which renders it an ENCrCLOPBWA OS USEFUL, SCIENTIFIC, and MECHANICAL INFORMATION, for present as well as future reference. Hoping to stimulate our readers to greater activity in spreading the circulation of the Scientific American, we offer the following Splendid Prizes for the largest list of mail subscribers sent iu by the flrat of January next.— JlOOwillbe given forthelargeat list. $75 for the second largest list. $50 for the third ditto, $45 for the fourth ditto. : $40 for the fifth ditto. $35 for the sixth ditto. $30 for the seventh ditto. $25 for the eighth ditto. $20 for the ninth ditto. $15 for the tenth ditto. $10 for the eleventh ditto. $5 for the twelfth ditto. The cash will be paid to the order of the successful competitors, immediately after January 1st, 1854. These prizes are worthy of an honorable and en-ergetio competition, and we hope our readers will not let an opportunity so favorable pass without attention. Terms ! Terms! Terms I One oopy, for Oae Tear $3 " Six Months $1 Five oopies, f orSix Months $4 Ten Copied for Six Months for $8 Ten Copies for Twelve Months, $18 fifteen Copies for Twelve Months, $22 Twenty Copies for Twelve Months, $28 Southern and Western Money taken at par for abscriptions, 01 Post OSes Stamps tsien at thir par value. "- Letters should be directed (post-paid) to MUNN CO., 123 Julton street, New York.