On the 5th of January next, the FOURTH VOLUME of the "NEW SERIES" of the SCIENTIFIC AMERICAN will be commenced. In announcing the above fact, the publishers embrace the opportunity to thank their old patrons and subscribers for the very liberal support they have hitherto extended to this journal; placing it, as they have, far beyond that of any other publication of the kind in the world, in point of circulation. The extent of the circulation evinces the popularity of the paper; and while our readers eeem satisfied with the quantity and quality of mutter they get in one year's numbers (comprising 32 pages and costing only $2), the publishers are determined to still improve the paper during the coming year. Tlie SCIENTIFIC AMERICAN has the reputation, at home and abroad, of being the best weekly publication devoted to mechanical and industrial pursuits now published, and the publishers are determined if labor and enterprise will doit) to keep up the reputation they have earned during the RKTEEN YEARS they have been connected with its publication. TO THE INVENTOR! The SCIENTIFIC AMERICAN is indispensable to every inventor, as it not only contains illustrated descriptions of nearly all the best inventions as they come out, but each number contains an official list of the claims of all the patents issued from the United States Patent Office during the week previous; thus giving a correct history of the progress of inventions in this countrj*. We are alsoreceiving, every week, the best scientific journals of Great Britain, Trance and Germany; thus placing in our possession all that is transpiring in mechanical science and art in those old countries. We shall continue to transfer to our columns copious extracts from these journals of whatever we may deem of interest to our readers. TO THE MECHANIC AND MACHINIST ! No person engaged iu any of the mechanical pursuits should think of u doing without " the SCIENTIFIC AMERICAN. It costs but four cents per week ; every number contains from six to ten engravings of new machines and inventions, which cannot be found in any other publication. It is an established rule of the publishers to insert none but original engravings, and those of thefirstclassinthe art, drawn and engraved by experienced persons under their own supervision. TO THE CHEMIST AN1> ARCHITECT ! Chemists and architects will find the SCIENTIFIC AMERICAN a useful journal to them. All the new discoveriesin the science of chemistry are given in its columns, and the interests of the architect and carpenter are not overlooked ; but all the new inventions and discoveries appertaining to these pursuits are published from week to week. TO THE MILLWRIGHT AND MILL-OWNER ! Useful and practical information appertaining to the interests of millwrights and mill-owners will be found published in the SCIENTIFIC AMERICAN, which information they cannot possibly obtain from any other source. To tins class the paper is specially recommended. TO THE PLANTER AND FARMER ! Subjects in which planters and farmers are interested will be found discucsed in the SCIENTIFIC AMERICAN ; most of the improvements in agricultural implements being illustrated in its columns. TO THE MAN OF LEISURE AND THE MAN OP SCIENCE Individuals of both these classes cannot fail to be interested in the SCIENTIFIC AMERICAN, which contains the latest intelligence on all subjects appertaining to the arte and sciences, both practical and theoretical; all the latest discoveries and phenomena which come to our knowledge being early recorded therein. TO ALL WHO CAN READ ! Everyone who can read the English language, we believe, will be benefitted by subscribing for the SCIENTIFIC AMERICAN, sad receiving its weekly visits; and while we depend upon all our old patrons renewing their own subscriptions, we would ask of each to send ue one or more new names with his own. A single person has sent UB as many as 160 mail subscribers, from one place, in a single year ! The publishers do not expect every on will do as much ; but it the 3,500 subscribers, whose subscriptions expire with the present volume, will each send a single name with their own, they will confer a lasting obligation upon us, and they will be rewarded for it in the improvement w shall be enabled to make in the paper by thuB increasing our receipts. The following are the TKRMS. To mail subscribers: Two Dollars a Year, or Une Dollar for Six Months. One Dollar pays for one complte volume of 416 pages ; two volumes comprise one year. The volumes commence on the .firsi of JANUARY and JDI-T. CLUB RATES. Five Copies, for Six Months...........................$4. Ten Copies, for Six Months...........................$8 Ten Copies, for Twelve Months.....................$15 Fifteen Copies for Twelve Months.........-........$22 Twenty Copies, for Twelve Months................$28 For all clubs of Twenty and over, the yearly subwriptiou is only $1 40. Names can be sent in at different times and from different Post-offices; Specimen copies will be sent gratia to any part of the country. Southern, Western and Canadian money or Post-office stamps taken at par for subscriptions. Canadian subscribers will please to remit twenty-six cents extra on each year's subscription to prc-pny postage. MUNN & CO., Publishers, No. 37 Park-row, New York.