Dr. Lohmann gives some exhaustive notes about prismatic ice. He found it a product of the fall months. He thinks all the observations show that "the beginning of all prismatic formation in the ice may be looked for in the changes of temperature in the cave at the time of the formation of the ice. These cause the everywhere recognized splitting, vertically to the outer surface. The further development hangs, as shown by Hagenbach and Emden, on the attempt of the neighboring cells, to join into larger unities. The increase of the larger crystals is finally prevented by the melting out of the openings between the separate crystals. Through this may be explained the difference in the prismatic ice in different parts of the same cave." Regierungsrath Franz Kraus, in 1895, wrote a short essay on glacières in _Höhlenkunde_. He seems to have seen but few glacières himself, and considers the scientific side of the question by no means solved as yet. He says: "The last word will not be spoken by the geographers and the Alpine climbers * * * but by the physicists, in whose field both questions really belong. Only then, when the physical circumstances of the formation of the ice in glacières have been so thoroughly understood, that under the same circumstances it may be possible to build artificial glacières, only then could one say: the glacière question is definitely settled. The best proof is always experiment." He lays down several dicta which he says are universally recognized, among which is this: "2. The ice formations in the débris heaps of basaltic mountains are summer ice formations. The evaporation of the infiltration water is recognized on all sides as the cause of this ice." I differ in opinion from Herr Kraus about this matter, and think that, on the contrary, every proof shows that the ice of basaltic taluses is not a summer formation and is not due to evaporation. Herr Kraus also says: "The _Eishöhlen_ resemble so little the _Windröhren_, that for these a proper name is quite correct. Just as one cannot draw a sharp line between _Einstürzschlünden_ and _Einstürzdolinen_, so one cannot draw a sharp line between _eishöhlen_ and _windröhren_. A stagnation of cave air does not exist, and no cave student would pretend to say it existed. The circulation of air may in certain caves take place almost entirely through the mouth and it then depends largely on the shape of the latter; in other caves are crevices and erosion holes, which allow a circulation of air. Again in other caves air may come through the floor into the cave, as is proved by certain places always remaining free from ice."