Harry J.—Any mineral or any package containing minerals, shells, or similar matter, not exceeding four pounds in weight, may be sent by mail at the rate of one cent for each ounce. In exchanging stones from different States, it would always be better to send some specimen of interest in itself, and one which represents the character of some mine or of celebrated ledges or quarries within the State limits. For example, it would be much more interesting to have a specimen in your collection labelled, "Marble from Vermont" or "Iron Ore from Connecticut," than to have the same specimen simply labelled a stone from either of those States. From Iowa, where you live, a specimen of galenite from the lead mines would be interesting, or any mineral found in abundance near your home.
A. J. Gibbs.—The first canal in the United States is supposed to have been built in the Connecticut Valley to allow boats to pass around the falls at South Hadley and around Turner's Falls at Montague. In February, 1792, the Massachusetts Legislature passed an act incorporating a company for the building of this canal, and operations were soon after commenced at South Hadley. The engineer was Benjamin Prescott, of Northampton. The Middlesex Canal, from Boston to Lowell, was built a few years later, and also a portion of the Mohawk Valley Canal. In 1797 six miles of the latter were completed, making a passage around rapids on the Mohawk River for boats of fifteen tons.
The first canals were built by the ancients for purposes of irrigation, but at a very early period they were also used as navigable channels. The royal canal of Babylon, built about 600 b.c., is one of the earliest mentioned in history. The Grand Canal of China, which is about 650 miles long, was built during the eighth century. At the changes of level the boats were dragged up inclined planes, and it was not until about 1480 that locks were invented by two Italian engineers. After this invention, by which one of the greatest impediments to canal navigation was removed, the construction of canals became general throughout Europe. One of the largest enterprises of the kind was that undertaken by Peter the Great during the first years of the eighteenth century: 1434 miles of canals were built, connecting St. Petersburg with the Caspian Sea and with inland districts.
The first canal was built in England in 1760, and at the present time there are about 47,000 miles of canals in Great Britain.
Favors are acknowledged from Frankie L. Garbutt, F. M. Elliot, Albert H. Hopkins, Josie Chesley, N. D. Sugden, A. H. Patterson, Gracie Mathews, May Arnold, Willie Derr, Florence E. Lewis, Calvin Colton W., Henry J. Nuhn.
Correct answers to puzzles have been sent by Harry H. Dickinson, Rebecca Hedges, Martie H., Thomas M. Armstrong, Allie Maxwell, Hugh Pitcairn, Will B. Shober, Grace B., William Harris, Walter P. Hiles, C. Wieland.