TABLE OF CONTENTS XI 



Chapter XII. Miscellaneous Problems (Continued). PAQE 



Prefatory 247 



Arithmetical. Digit Questions. Two Examples 247 



Restorations, Class A. Four Examples 248 



Restorations, Class B. Five Examples 249 



Restorations, Class C. Two Examples 252 



Calendar Problems. Two Examples 253 



Geometrical. The Five Disc Problem 253 



Tesselation with Super-Dominoes 255 



Dissections 256 



The Window Reader 260 



Compass Problems 262 



Chapter XIII. Calculating Prodigies. 



Calculating Prodigies. Authorities 264 



John Wallis, 1616-1703 265 



Buxton, circ. 1707-1772 265 



Problems solved by 266 



Methods of 267 



Fuller, 1710-1790 268 



Ampere, Gauss, Whately 268 



Colburn, 1804-1840 269 



Problems solved by 269 



Power of Factorizing Numbers 270 



Bidder, 1806-1878 271 



Career of 271 



Problems solved by 273 



The Bidder Family 275 



Mondeux, Mangiamele 276 



Dase, 1824-1861 276 



Problems solved by 277 



Scientific Work of 278 



Safford, 1836-1901 278 



Zamebone, Diamandi, Ruckle 279 



Inaudi, 1867- 279 



Problems solved by 280 



Expression of Numbers by Four Squares 280 



Nature of Public Performances 280 



Types of Memory of Numbers 281 



Bidder's Analysis of Methods used 282 



Preferably only one step at a time 283 



Multiplication. Examples of 283 



Division. Digit-Terminals . . . - 285 



Digital Method for Division and Faotors , 285 



Square Boots. Higher Boots 286 



Compound Interest 288 



Logarithms 289 



Suggested Law of Rapidity of Calculation 290 



Requisites for Success • 291 



