Question Sam Loyd's Cyclopedia of Puzzles Answer
W3N Home Introduction Puzzles by Page Puzzles by Title Puzzles by Type Feedback
Proposition: What is the difference in weight of six dozen dozen pounds of feathers and half a dozen dozen pounds of gold?

THRE IS ONE OF THE old-time problems of our great - grand - daddies which has been passed down through successive generations without any one's having the temerity to question the correctness of the accepted answer which is that "a pound is a pound the world over." It recently so happened, however, that a little boy from Boston, who was a juvenile puzzlist, had the antique gem sprung upon him and gave an answer which took the wind out of the sails of his doting old grandfather.

Of course, you have asked and been asked so often regarding the difference between six doz. Pounds of feathers and half a dozen pounds of gold, that the answer comes spontaneously without a moment's hesitation, and yet, if the question is asked with all seriousness, with prizes for the best explanations just to encourage correct work, it is safe to say that it will he discovered that no one has really attempted to prove the old problem since its first appearance in 1614.

Now what is the difference in weight between six dozen dozen pounds of feathers and half a dozen dozen pounds of gold?

Now, in this particular case, I searched through the musty corners of my brain to select a few antique illustrations, with a rich chestnutty flavor, to revive, or rather arouse that interest which one of those good old familiar puzzles never fails to elicit and which are often associated with pleasant memories of the long ago. My object, however, was also to show that by giving a new set of teeth to some of these old saws, to prove that their sharpness has been overlooked by many of our puzzlists, in this as well as in other instances which will be mentioned.

Grandfather's query as to the difference in weight between six dozen dozen pounds of feathers and half a dozen dozen pounds of gold, shows that the catch of six dozen dozen being 864, while half a dozen dozen would be but half a gross, does not satisfy the question, because gold is weighed by troy weight, while feathers are weighed by avoirdupois weight. In this case the time honored reply of “A pound is a pound the world over,” will not apply.

To be exact, six dozen dozen pounds of feathers weigh 864 pounds avoirdupois, while 72 pounds troy of gold is only equal to 59 pounds 3 ounces and 400 1/2 grains, so the actual difference would be 804 pounds 12 ounces and 30 grains.

The average person has no conception of the relationship between troy and avoirdupois weight. Some believe that the pounds weigh the same, but in one case is divided into sixteen parts and in the other case into twelve to represent ounces. More people, however, believe that the ounces are the same, so that the avoirdupois pound weighs sixteen ounces while the troy pound weighs but twelve. Of course, neither case is correct, as it will be found that the connecting link between the two systems turns upon the fact that a pound avoirdupois weighs 7,000 grains, while a pound troy weighs only 5,760 grains.

[Page 16]