No competent chemist would use the meager data available to assert that the 1954 and 1956 fragments had an identical origin, or that they were originally composed only of pure tin. A quantitative analysis theoretically could show that a given sample is composed entirely of a certain element such as tin, but if the sample contains only 90 per cent tin, 10 per cent obviously consists of other elements, and the specimen is not 100 per cent pure tin. With so few facts available, the actual identity of the silver rain can only be guessed at, but overwhelming evidence indicates that it was made right here on earth. The _Handbook of Chemistry and Physics_ lists a large number of possibilities. At least 5 alloys of tin and lead, without antimony, have densities between 9.43 and 10.33, like the 1956 fragments. Ordinary “plumber’s solder” is 67 per cent lead, 33 per cent tin, and has a density of 9.4. “Tinman’s solder” is 67 per cent tin and 33 per cent lead. Many aluminum solders have neither antimony nor lead, but contain tin in percentages ranging from 50 to 97 per cent, combined with varying proportions of zinc, aluminum, copper, cadmium, or phosphorus. One judicial-minded investigator of flying saucers gently pointed out to the editor of the _UFO Critical Bulletin_ that the use of the word “proved” for the extraterrestrial origin of the silver rain was premature, and suggested the need for obtaining and publishing a complete analysis before drawing any conclusions. The editor responded with the peculiar logic of the xenochemist: “What more is necessary to convince so severe and thickheaded person as Dr. ----? Would be necessary a statement in conjunction with some highly worldly considered scientist? ... Would be necessary a statement in conjunction from Eisenhower, Khrushchev and the Pope?--This he’ll never get of course. Would be necessary a UFO landing on his private garden?”[XI-17] Another type of colored substance is the “blue rain” that sprinkled a thirty-mile stretch of countryside near London on September 9, 1962. Falling without warning from clear skies, it left a blue stain that wouldn’t wash off. Investigation showed that the substance came from jet planes taking part in Britain’s annual giant air show at Farnborough. The jets were using the blue dye to color their vapor trails and make a more spectacular display. _Other Mysterious Fragments_