Reprints of slide rule instructions, for the use of collectors, educators and students. All ephemera is currently archived in the International Slide Rule Museum Library. Instruction manuals, for the most part, are no longer available, Slide rule production ended in the mid 1970's and instruction manuals have deteriorated and are rapidly disappearing over time. The slide rule models themselves , now considered vintage math instruments, are still in abundance, and in the hands of private collections, museums, and many family homes. These volumes, organized by manufacturers, provide instructions for the most popular models, as well as some special designs. The scans from the faded and wrinkled manuals, have been "restored" digitally in order improve their clarity to provide decent black printing on white pages. All "noise", speckles, staple marks, etc., have been cleaned off the original scans, to improve the reader's experience. Where required, as in this volume, permissions have been obtained from manufacturers that are still in existence. Instruction Books (in English, German and Spanish languages) contained in Volume 7 Book 1 - Pages 1-19 Instructions for the Use of the Aristo Slide Rules (Rietz Pattern). Circa 1930. 18 pages. Book 2 - Pages 20-24 Aristo PUCK No. 810, 811 and Simplex No. 812. 4 pages. Book 3 - Pages 25-54 Instructions for the Use of the Aristo Studio No. 868, 0968 and 01068. 29 pages. Book 4 - Pages 55-86 Instructions for the Use of the Aristo Multilog No. 870, 0970 and 01070. 31 pages. Book 5 - Pages 87-110 Instructions for the Use of the Aristo Scholar No. 903, 0903 LL, 0903 VS, and 0903 VS-2. 24 pages. Book 6 - Pages 111-139 Instructions for the Use of the Aristo Commerce No. 845, 0905, Commerce II No. 955 and 965. 28 pages. Book 7 - Pages 140-173 Instructions for the Use of the Aristo Trilog No. 0908. 33 pages. Book 8 - Pages 174-198 Instructions for the Use of the Aristo Electro No. 815 and 915. 24 pages. Book 9 - Pages 199-215 Instructions for the Use of the Aristo Darmstadt No. 867U, 967U and 1067U. 16 pages. Book 10 - Pages 216-240 Manual of Instructions. Aristo Multilog Slide Rule No. 970. Charvoz-Roos Corporation. 24 pages. Book 11 - Pages 241-297 Instructions for the Use of the Aristo Hyperbolog No.0971 and Hyperlog No. 0972. 56 pages. Book 12 - Pages 298-302 Instructions for the Use of the Aristo Projection Slide Rule. 4 pages. GERMAN and 7 other languages. Book 13 - Pages 303-307 Anleitung Zum Taschenrechenstab Aristo-Rietz Nr. 89. 4 pages in German. Book 14 - Pages 308-312 Handledning Till Fick-Räknestickorna Aristo-Flex Nr 807, Aristo-Darmstadt Nr 867. 4 pages. Book 15 - Pages 313-343 Anleitung Zum Rechenstab Aristo Commerz Nr. 0905, 845, 955, 1055, 965. 30 pages in German. Book 16 - Pages 344-381 Anleitung Zum Rechenstab Aristo Bischolar 906 und Bischolar LL 906 LL. 37 pages in German. Book 17 - Pages 382-414 Anleitung Zum Rechenstab Aristo Trilog 908. 32 pages in German. Book 18 - Pages 415-445 Anleitung Zum Rechenstab Aristo Studiolog 0969. 30 pages in German. Book 19 - Pages 446-487 Anleitung Zum Rechenstab Aristo Hyperbolog 0971. 41 pages in German. Book 20 - Pages 488-494 Calculador De Porcentajes, Aristo 603 y 604. 6 pages in Spanish. Book 21 - Pages 495-539 Instrucciones Para el Uso de la Regla de Calculo. Aristo 870, 0970, 01070 and 0971. 44 pages in Spanish.