100 YEARS AGO ⃛ owing to the kindness of Dr. Hampson, we have been furnished with about 750 cubic centimetres of liquid air, and, on allowing all but 10 cubic centimetres to evaporate away slowly, and collecting the gas from that small residue in a gas-holder, we obtained, after removal of oxygen with metallic copper and nitrogen with a mixture of pure lime and magnesium dust, followed by exposure to electric sparks in presence of oxygen and caustic soda, 26.2 cubic centimetres of a gas, showing the argon spectrum feebly, and, in addition, a spectrum which has, we believe, not been seen before. ⃛ it may be concluded that the atmosphere contains a hitherto undiscovered gas with a characteristic spectrum, heavier than argon, and less volatile than nitrogen, oxygen, and argon; the ratio of its specific heats would lead to the inference that it is monatomic, and therefore an element. If this conclusion turns out to be well substantiated, we propose to call it “krypton”, or “concealed.” Its symbol would then be Kr.

From Nature 9 June 1898.

50 YEARS AGO The practice of the whalers is to try to catch the largest whales — the gunner who does this gains in reputation; but any whale is better than none, since the factory ships have to be filled with oil. Since the average length of the whales killed is decreasing, it must be concluded that either the larger whales are becoming more difficult to catch or that they have been pretty well killed off. The former assumption cannot stand, for against powerful modern catchers the bolting whale stands no chance. It must take frequent breaths while travelling at speed, remaining practically at the surface all the time, and so can be easily followed and run down. With regard to the latter assumption, the remarks made to me after the last Antarctic season by a very experienced whaler are pertinent. He told me that blue whales were not what they used to be, and that the enormous animals of past years were either extremely scarce or non-existent. ⃛ The inevitable conclusion is that the larger animals have been killed off, and that the survivors do not live long enougho attain the great size of former years.

From Nature 12 June 1948.