Popular Science Monthly
��Coaxing Music from a Pile of Rocks
��AMR. FROST, of Mar- blehead, Mass., was en- gaged in clearing his land of some huge, flat rocks, when he accidentally struck one with his hammer. It emitted a clear musical note. He struck another in the same way. The tone given out was equally clear and sweet but different in pitch. Trials with other stones of different shapes and sizes convinced him that it was possible to arrange the stones so as to get the notes of the scale.
After various experiments he piled the stones as shown in the accompanying photo- graph, securing thus a primi- tive instrument that any cave-man might have envied.
���Household Bookless Bookkeeping on the Poker-Chip Principle
ANEW system of bookless bookkeeping, designed especially for the housewife, happily coincides with the demand for careful record keeping in order to cut down expenditures to a wartime basis. This new system substitutes for old fashioned juggling with figures the simplicity and vividness of account-keeping with poker chips.
With the new method, books are entirely eliminated. The equipment con- sists of a box containing twenty- eight compartments to show ex- penditures for groceries, meats milk, butter, eggs, and other items of house- hold expense, and seven additional com- partments to hold slips representing various denominations from ten dollars down.
When a purchase is made, slips indicating the amount are placed in the appropriate compartment. At the end of the month, the housewife can determine the amount soent for
��The "piano" made of a heap of stones (arranged so that the tones of the natural scale are produced by hammer-blows
��each item by counting the amounts, in the different compartments.
If the article is charged, the right amount is placed in the proper compartment, and a corresponding amount in the "Charged" compartment. Thus there is a correct tab on the amount owed as well as on the expenditures.
After the housewife has determined by a two or three months' trial about what her normal expenses are for the various items of expenditure, she may change to the budget system. Slips totaling the proper amount are placed in the various compartments, and, as expenditures are made, the amount is removed. The slips remaining show at all
���times the sum left in each "appropriation," so that economy or freedom in spending may be observed. If the slips in any com- partment run short, others may be "bor- rowed" from a com- partment with a sur- plus, a "due" check being put in to show the indebtedness. The amounts remain- ing at the end of the month indicate the sur-
��plus, and the due checks The bookless bookkeeping outfit for the shortages. Thus all housewife who dislikes keeping accounts figuring is eliminated.