“Thirty days hath September, April, June, and November,” etc., and many other rhymes and devices are used to aid the memory to decide how many days are in each month of the year.
Herewith is illustrated a very simple method to determine the number of days in any month.
Place the first finger of your right hand on the first knuckle of your left hand, calling that knuckle January; then drop your finger into the depression between the first and second knuckles, calling this February; then the second knuckle will be March, and so on, until you reach July on the knuckle of the little finger, then begin over again with August on the first knuckle and continue until December is reached.
Each month, as it falls upon a knuckle, will have 31 days and those down between the knuckles 30 days with the exception of February which has only 28 days. —Contributed by Chas. C. Bradley, West Toledo, Ohio.
The Knuckles Designate the 31 Day Months
Excerpt from the book: THE BOY MECHANIC VOLUME I 700 THINGS FOR BOYS TO DO WITH 800 ILLUSTRATIONS 1913, BY H. H. WINDSOR CHICAGO POPULAR MECHANICS CO. PUBLISHERS