i 4 LIFE AND HABIT. 



and talk, with hardly an effort — some show such an 

 instinctive aptitude for arithmetic that, like Zerah Col- 

 burn, at eight years old, they achieve results without 

 instruction, which in the case of most people would 

 require a long education. The account of Zerah Col- 

 burn, as quoted from Mr. Baily in Dr. Carpenter's 

 " Mental Physiology," may perhaps be given here. 



" He raised any number consisting of one figure pro- 

 gressively to the tenth power, giving the results (by 

 actual multiplication and not by memory) faster than 

 they could he set dcnun in figures by the person appointed 

 to record them. He raised the number 8 progressively 

 to the sixteenth power, and in naming the last result, 

 which consisted of I 5 figures, he was right in every 

 one. Some numbers consisting of two figures he raised 

 as high as the eighth power, though he found a diffi- 

 culty in proceeding when the products became very 

 large. 



"On being asked the square root of 106,929, he 

 answered 327 before the original number could be 

 written down. He was then required to find the cube 

 root of 268,336,125, and with equal facility and 

 promptness he replied 645. 



" He was asked how many minutes there are in 48 

 years, and before the question could be taken down he 

 replied 25,228,800, and immediately afterwards he 

 gave the correct number of seconds. 



"On being requested to give the factors which would 

 produce the number 247,483, he immediately named 

 941 and 263, which are the only two numbers from 

 the multiplication of which it would result. On 



