The application of cold storage for preservation purposes is, however, no novelty; for nature ages ago set us the example, and of this we have been lately reminded afresh by the discovery announced by Dr. Herz of a mammoth in Siberia, which, despite the thousands of years which have elapsed since it was originally overwhelmed and frozen, is described as being in a marvellous state of preservation. Thus we are told that "most of the hair on the body had been scraped away by ice, but its mane and near foreleg were in perfect preservation and covered with long hair. The hair of the mane was from four to five inches long, and of a yellowish brown colour, while its left leg was covered with black hair. In its stomach was found a quantity of undigested food, and on its tongue was the herbage which it had been eating when it died. This was quite green." Considering that certainly more than eight thousand years had elapsed since this creature was peacefully consuming what proved to be its last meal, nature's method of cold storage must indeed be regarded as unsurpassable in the excellence of its results. I believe it was in the year 1884 that the first attempts were made to follow more closely and in greater detail the precise effect upon different bacteria of submitting them to temperatures of such a low degree as -130° C., obtained by means of solid carbonic acid. These experiments were carried out by Pictet and Young, and are recorded in the _Comptes Rendus_ of the Paris Academy of Sciences. They differ from those which we have so far been considering, inasmuch as the bacteria were not frozen in water, but in culture-material, or, in other words, like the mammoth, whilst enjoying a midday meal! One of the micro-organisms experimented with was a bacillus known at that time as the rinderpest bacillus, capable of producing disease in animals when inoculated into them and existing both in the spore and bacillar form. Pictet and Young specially state that the spore form was present in the specimens employed by them, and hence the fact that this micro-organism was alive after being frozen and exposed to this low temperature of -130° C. for the space of twenty hours is not, perhaps, so surprising when we bear in mind the remarkable feats of endurance exhibited by spores which have with justification obtained for them a prominent place amongst the so-called curiosities of bacteriology. But of more interest than their mere survival in these circumstances is the fact that, on being restored to animation--or, in other words, released from their ice-prison--these bacteria were discovered to have retained all their pathogenic properties, this period of enforced rigidity having in no way affected their disease-producing powers.