هذه الصورة (أو كل الصور في هذا التصنيف/الصفحة) غير واضحة، أو مبهَرة جدا، أو غامقة جدا، أو لا تظهر بصفة جيّدة ما يجب إن توجد صورة أخرى أحسن، فكّر في إستعمالها تلك عوضا عن هذه. وإلّا حاول أن تجد صورة بديلة ذات رخصة حرّة من الأنترنت.
صفحة الوصف الأصلية كانت هنا، تشير جميع أسماء المستخدمين التالية إلى en.wikipedia.
This is a scan of a Pickett pocket slide rule, done by me, Benjamin Crowell, in 2005. The slide rule does not have a copyright notice on it, and works published in the U.S. without a copyright notice before 1977 are in the public domain. I therefore think the slide rule itself is in the public domain under U.S. law. I'm making my scan available under the GFDL license.
(This is a scan of a Pickett pocket slide rule, done by Benjamin Crowell in 2005. The slide rule does not have a copyright notice on it, and works published in the U.S. without a copyright notice before 1977 are in the public domain. I therefore think the )
سجلُّ الرَّفع الأصيل
Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version.
Click on date to download the file or see the image uploaded on that date.
(del) (cur) 19:33, 23 April 2005 . . en:User:Bcrowell Bcrowell ( en:User_talk:Bcrowell Talk) . . 558x152 (20510 bytes) (This is a scan of a Pickett pocket slide rule, done by me, Benjamin Crowell, in 2005. The slide rule does not have a copyright notice on it, and works published in the U.S. without a copyright notice before 1977 are in the public domain. I therefore think)
(del) (rev) 19:24, 23 April 2005 . . en:User:Bcrowell Bcrowell ( en:User_talk:Bcrowell Talk) . . 634x174 (25206 bytes) (This is a scan of a Pickett pocket slide rule, done by Benjamin Crowell in 2005. The slide rule does not have a copyright notice on it, and works published in the U.S. without a copyright notice before 1977 are in the public domain. I therefore think the )
(del) (rev) 19:18, 23 April 2005 . . en:User:Bcrowell Bcrowell ( en:User_talk:Bcrowell Talk) . . 652x203 (27548 bytes) (This is a scan of a Pickett pocket slide rule, done by Benjamin Crowell in 2005. The slide rule does not have a copyright notice on it, and works published in the U.S. without a copyright notice before 1977 are in the public domain. I therefore think the )
الشروحات
أضف شرحاً من سطر واحد لما يُمثِّله هذا الملف
עזרים לחישובים אריתמטיים לאורך ההיסטוריה (ימין, מלמעלה למטה): תרשים של מוטות מנייה סיניים ששימשו עוד בתקופת המדינות הלוחמות, חשבונייה מרומא העתיקה, פסקלין מ-1652 (שמאל, מלמעלה למטה): מנוע הפרשים מ-1879, סרגל חישוב ומחשבון מודרני (4)
La bildo estas kopiita de wikipedia:en. La originala priskribo estas: This is a scan of a Pickett pocket slide rule, done by me, Benjamin Crowell, in 2005. The slide rule does not have a copyright notice on it, and works published in the U.S. without a c