This section is from the book "A Library Of Wonders And Curiosities Found In Nature And Art, Science And Literature", by I. Platt. Also available from Amazon: A library of wonders and curiosities.
If the number 11 be multiplied by any one of the nine digits, the two figures of the product will always be alike, as appears from the following example:11 11 11 11 11 11 11 11 11 123456789
11 22 33 44 55 66 77 88 99
Now, if another person and yourself have fifty counters apiece, and agree never to stake more than ten at a time, you may tell him, that if he will permit you to stake first, you will always undertake to make the even century before him.
In order to this you must first stake one, and remembering the order of the above series, constantly add to what he stakes as many as will make one more than the numbers 11, 22, 33, etc. of which it is composed, till you come to 89; after which, the other party cannot possibly make the even century himself, or prevent you from making it.
If the person who is your opponent have no knowledge of numbers, you may stake any other number first, under 10, provided you afterwards take care to secure one of the last terms, 56, 67, 78, etc.: or you may even let him stake first, provided you take care afterwards to secure one of these numbere.
This recreation may be performed with other numbers; but, in order to succeed, you must divide the number to be attained, by a number which is an unit greater than what you can stake each time; and the remainder will then be the number you first stake. Suppose, for example, the number to be attained is 52, and that you are never to add more than six; then dividing 52 by 7, the remainder, which is 3, will be the number you must stake first; and whatever the other stakes, you must add as much to it as will make it equal to 7, the num. ber by which you divided; and so on.
A Person in Company having privately put a Ring on one of his fingers, to Name the Person, the Hand, the Finger, and even the Joint on which it is placed.
Desire a third person to double the number of the order in which the wearer of the ring stands, and add 5 to that number, then multiply that sum by 5, and to the product add 10. Let him then add 1 to the last number, if the ring be on the right hand, and 2 if on the left, and multiply the whole by 10: to this product he must add the number of the finger, beginning with the thumb, and multiply the whole again by 10. Desire him then to add the number of the joint; and lastly, to increase the whole by 35.
This being done, he is to declare the amount of the whole from which you are to subtract 3535; and the remainder will consist of four figures, the first of which will give the place in which the person stands, the second the hand, 1 denoting the right, and 2 the left hand, the third number the finger, and the fourth the joint.
Example.
Suppose the person stands the second in order, and has put the ring on the second joint of the little finger of the left hand:
Double the order is 4 Add.............. 5
9 Multiply by........ 5
45 Add............. 10
55 Number for left hand 2
57 Multiply by,..... 10
570 Number of finger .. 5
575 Multiplyby...... 10
5750 Number of joint .. 2
5752 Add............ 35
5787 Subtract.........3535
Hence it will appear that the first 2 denotes the second person in order, the second 2 the left hand, 5 the little finger, and 2 the second joint.
 
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