Bomb
2 of the 7 encyclopedias on this shelf carry an entry for Bomb. Both are reproduced below, so you can see where they agree and where they differ.
Collier's New Encyclopedia (1921)
Important: Safety Warning This page contains instructions involving gunpowder or other explosive or pyrotechnic compositions. Preparing explosives as described has caused severe injuries and deaths, and is illegal in most places. This information has been left in for historical purposes but should not be acted upon. in ordnance, the same as a bomb shell; a hollow iron ball, spheroid, or anything similar, filled with gunpowder, and provided with a timed percussion fuse. It is fired from a mortar or howitzer. Bombs were used at the siege of Naples in 1434. Mortars for throwing bombs were first cast in 1543. Modern political upheavals have induced a traffic in packages of explosives, which have been christened bombs. These terrific agents of destruction have been used with murderous effect in the larger European cities: Petrograd, Madrid, and Paris; also in Chicago. The anarchists have regularly established factories for the production of the missiles. The usual method of construction is to fill a hollow sphere with some high explosive together her with pieces of scrap iron, nails, bullets, s, bullets, or an anything that will wound. The explosives used are generally nitroglycerine, fulminate of mercury, etc. The most deadly of all the agents, however, is a bomb made with chlorate of potash and picric acid.
Aiton's Encyclopedia (1910)
or Shell, a missile thrown by guns of great size, formerly known as mortars. The old-fashioned bomb of cast iron was hollow, and contained a charge of powder. A time fuse connected with the powder was ignited by the discharge of the gun. It was cut to a proper length to fire the powder within the bomb at the desired moment. The fragments of the bursting bomb were likely to do more damage than a solid ball, especially as it might be thrown upward so as to fall within inclosures and reach those behind a protecting wall. In place of the spherical bomb the elongated shell thrown by a rifled cannon is now in general use. During a bombardment it is customary for all not needed on the walls to man the guns, to seek refuge in underground or bomb-proof retreats. In modern warfare it is considered humane to give twenty-four hours' notice of the intended bombardment of a town, that women, children, and non-combatants may be removed to a place of safety. See Shell 2026 Editor's Note: The word outgrew this entry beyond recognition. Bombs left the mortar for the aeroplane, and in August 1945 two of them — Hiroshima and Nagasaki — destroyed whole cities at a stroke and reordered world politics around the threat of their use. "The bomb," with no other qualifier, now means only one thing. (Ed: BR 2026-07-14)