"Machine d'Arithmétique" of 1652

Excellent replica of world's first mechanical calculator by Blaise Pascal, Paris. The first mechanical calculator for addition and subtraction produced in series was developed by Blaise Pascal of Paris in the year 1642. Because the machine was designed mainly for calculating currency – Pascal's father was a tax collector, and his son had designed the machine to simplify his work – the individual digit positions were marked in accordance with English currency, which was still prevalent in France at the time. The first location was called "Deniers" (Pence = up to 12), the second "Sols" (Shilling = up to 20), and the other four positions for the tens units (livres = pounds). On this machine from 1652, the first two positions for Deniers and Sols were omitted in order to be able to add and subtract only greater even amounts (gold pieces). – The arithmetic procedure began at the zero position of the all sight openings by rotating the digit wheels. To add, the ruler located on the indicator rolls was pushed upward. The indicator rolls were marked with digit sequences in two rows. The bottom row went from 0 to 9 (addition), beginning at the left with zero and ascending, and the upper row went from 9 to 0 (subtraction). The same mechanical handling thus applied for both arithmetical operations. – A pin was inserted in the gap in the spokes of the aligning wheel for the respective digit, and turned until it reached the stop motion device. The ruler was simply pushed down to switch from addition to subtraction. The mode of operation remained the same. Pascal's calculators had decimal carry from the very beginning, and could also be used for multiplication, which was, however, an extremely difficult task. – A superb collector's item and exhibition piece!

布雷克拍品等级是为了方便竞买人判断拍卖品的成色而设置的。布雷克等级用1到6级来标注外观和功能的成色，(从非常好到非常差)。 在目录图册里用括号里的2个数字来表示，前一个数字表示外观成色的级别，后一个数字表示功能成色的级别。如(3/2)表示外观成色是3(满意的)，功能成色2(好)。 成色 定义参照下列标准： 1 - 非常好 (未使用过，没有使用痕迹) 2 - 好 (新，极少的使用痕迹) 3 - 满意的 (普通的使用痕迹) 4 - 及格的 (明显的使用痕迹，某个非主要部件是后配的) 5 - 有缺陷的 (极明显的使用痕迹, 某个主要部件是后配的，功能上有缺陷，需要修理) 6 - 非常差 (严重破损, 缺少重要部件)