APRIL 1959
PLANET OR ESCAPEE?— “In their relatively brief acquaintance with Pluto, astronomers have begun to doubt that this object is a planet at all. Pluto’s eccentric orbit is tilted at a considerable angle to the plane of the ecliptic, in which the orbits of the other planets lie. Even on its closest approach to our region of the solar system, it will shine no brighter than Triton, one of Neptune’s two satellites, suggesting that it is no larger. There is suspicion that Pluto is an illegitimate offspring of Neptune, a satellite that escaped, as two man-made satellites recently did, to ply its own orbit around the sun.
—Owen Gingerich

THE DEEPEST HOLE— “The crust of the earth is a relatively thin film over the earth’s interior. Its average thickness is some 10 miles, a mere 400th of the earth’s radius. Beneath the crust lies the mantle; important details of its composition and character are uncertain. These can only be determined by direct examination. The boundary between crust and mantle is the Mohorovicic discontinuity, known to earth scientists as the Moho. To obtain a sample of the mantle, we must drill a hole through the Moho: a Mohole. —William Bascom”
[NOTE: Work on the unfinished Mohole was abandoned in 1966.]

APRIL 1909
LIGHTER MONEY— “Experiments in abrasion conducted at the French mint have proved that aluminium coins will be less rapidly worn by use than coins of gold, silver, or even bronze. The metal’s extreme lightness is another advantage: it is four times lighter than silver. Hence aluminium coins could be carried in considerable quantities without inconvenience. The total nominal value of bronze 5 and 10 centime pieces in circulation is estimated to be about 56 million francs. It is proposed to replace some 50 million francs’ worth of these with aluminium coins of the same denominations. About 2,000 tons of aluminium, worth 44 cents a pound in blanks ready for stamping, will be required.”

VOICE RECOGNITION— “A safe lock has been invented which is provided with a phonographic mechanism so that it can be opened only by the voice of the owner. A mouthpiece like that of a telephone takes the place of a knob on the door, and this is provided with the usual needle, which travels in a groove in the sound record of the phonograph cylinder. Before the safe can be unlocked, the password must be spoken into the cylinder by the one who made the original record. The report does not state what would occur if the owner should come down to his office with a bad cold.”

APRIL 1859
SOME SAY ALUMINUM— “It is only a few years ago that this valuable metal was uncommon and expensive, owing chiefly to the difficulty of reducing it from its oxyde. We believe that about three years ago, its market value was no less than $18 per ounce. In a very outcast region of the world—on the west coast of cold Greenland—an aluminous mineral called cryolite has been discovered in great quantities, from which the metal can be reduced at a very limited cost, and a large factory has lately been erected at Battersea, England, by M. Gerhard, for this very purpose. He has been able to sell it for about one dollar per ounce. Aluminum is the lightest of all the metals. This quality should recommend it for coinage, to take the place of coins of the lowest value.”

PATENT AGENCY— “The United States Patent Office, located at Washington, is the storehouse and monument of the ingenuity of our countrymen. Because of the value of many of the inventions for which patents are sought, and the great necessity that the papers be carefully prepared, there has grown up a profession, the members of which are usually designated ‘patent agents’ or ‘patent solicitors,’ and who have become as much a necessity for the proper transaction of business with the Patent Office as the lawyers are in our courts of justice. We will here state, in reference to ourselves, what no one will presume to deny, that since 1846, the Scientific American Patent Agency Department has examined into the novelty of more inventions than any other patent agents now living in this country. We present to our readers an illustration of the interior view of the ‘Scientific American’ and patent agency office, New York.”