Johann Martin Zacharias Dase Eduard Kaiser

Johann Martin Zacharias Dase (June 23, 1824,

Hamburg (male), (female) en, Hamburger(s), Hamburgian(s) , timezone1 = Central (CET) , utc_offset1 = +1 , timezone1_DST = Central (CEST) , utc_offset1_DST = +2 , postal ...

– September 11, 1861, Hamburg) was a German

mental calculator Human calculator is a term to describe a person with a prodigious ability in some area of mental calculation (such as adding, subtracting, multiplying or dividing large numbers). The world's best mental calculators are invited every two ye ...

W. W. Rouse Ball Walter William Rouse Ball (14 August 1850 – 4 April 1925), known as W. W. Rouse Ball, was a British mathematician, lawyer, and fellow at Trinity College, Cambridge, from 1878 to 1905. He was also a keen amateur magician, and the founding ...

(1960) ''Calculating Prodigies'', in Mathematical Recreations and Essays, Macmillan, New York, chapter 13. He attended schools in Hamburg from a very early age, but later admitted that his instruction had little influence on him. He used to spend a lot of time playing

dominoes Dominoes is a family of tile-based games played with gaming pieces, commonly known as dominoes. Each domino is a rectangular tile, usually with a line dividing its face into two square ''ends''. Each end is marked with a number of spots (also c ...

, and suggested that this played a significant role in developing his calculating skills. Dase had

epilepsy Epilepsy is a group of non-communicable neurological disorders characterized by recurrent epileptic seizures. Epileptic seizures can vary from brief and nearly undetectable periods to long periods of vigorous shaking due to abnormal electrica ...

from early childhood throughout his life. At age 15 he began to travel extensively, giving exhibitions in Germany, Austria and England. Among his most impressive feats, he multiplied 79532853 × 93758479 in 54 seconds. He multiplied two 20-digit numbers in 6 minutes; two 40-digit numbers in 40 minutes; and two 100-digit numbers in 8 hours 45 minutes. The famous mathematician

Carl Friedrich Gauss Johann Carl Friedrich Gauss (; german: Gauß ; la, Carolus Fridericus Gauss; 30 April 177723 February 1855) was a German mathematician and physicist who made significant contributions to many fields in mathematics and science. Sometimes refer ...

commented that someone skilled in calculation could have done the 100-digit calculation in about half that time with pencil and paper. These exhibitions however did not earn him enough money, so he tried to find other employments. In 1844 he obtained a position in the Railway Department of Vienna, but this didn't last long since in 1845 he was reported in Mannheim and in 1846 in Berlin. In 1844, Dase calculated π to 200 decimal places over the course of approximately two months, a record for the time, from the

Machin-like formula In mathematics, Machin-like formulae are a popular technique for computing to a large number of digits. They are generalizations of John Machin's formula from 1706: :\frac = 4 \arctan \frac - \arctan \frac which he used to compute to 100 de ...

: :

\frac = \arctan \frac + \arctan \frac + \arctan \frac.

He also calculated a 7-digit

logarithm table In mathematics, the common logarithm is the logarithm with base 10. It is also known as the decadic logarithm and as the decimal logarithm, named after its base, or Briggsian logarithm, after Henry Briggs, an English mathematician who pioneered i ...

and extended a table of integer factorizations from 6,000,000 to 9,000,000. Dase had very little knowledge of mathematical theory. The mathematician

Julius Petersen Julius Peter Christian Petersen (16 June 1839, Sorø, West Zealand – 5 August 1910, Copenhagen) was a Danish mathematician. His contributions to the field of mathematics led to the birth of graph theory. Biography Petersen's interests i ...

tried to teach him some of

Euclid Euclid (; grc-gre, Εὐκλείδης; BC) was an ancient Greek mathematician active as a geometer and logician. Considered the "father of geometry", he is chiefly known for the '' Elements'' treatise, which established the foundations of ...

's theorems, but gave up the task once he realized that their comprehension was beyond Dase's capabilities.Preston, Richard, 2008, Panic in Level 4, p. 32. Gauss however was very impressed with his calculating skill, and he recommended that the ''Hamburg Academy of Sciences'' should allow Dase to do mathematical work on a full-time basis, but Dase died shortly thereafter. The book " Gödel, Escher, Bach" by Douglas Hofstadter mentions his calculating abilities. "... he also had an uncanny sense of quantity. That is, he could just 'tell', without counting, how many sheep were in a field, or words in a sentence, and so forth, up to about 30."

References

External links

– A biography of Zacharias Dase. {{DEFAULTSORT:Dase, Zacharias Mental calculators 1824 births 1861 deaths