Liquid Oxygen and its Uses

Abstract

AN article or product regarded as a scientific curiosity by one generation not infrequently becomes a commonplace of the next. The vacuum flask used by Dewar to preserve very cold liquids at normal pressure has become a household necessity for retaining the temperature of warm liquids, and, under modern mass-production methods, the glass flask is now obtainable at a remarkably low price. The metal vacuum vessel, with charcoal in connexion with the vacuous envelope, is less widely known. It is not suitable for the retention of hot liquids; but by reason of its relative robustness and of the large sizes in which it can be made, it is preferable to the glass form for the storage and transport of liquid oxygen or liquid air. Without question, the introduction of the metal vessel has rendered possible such expansion in the commercial and scientific uses of liquid oxygen as is now slowly proceeding. That the importance of the metal vacuum bottle is fully realised, becomes clear upon a perusal of the recently published Report of the Oxygen Research Committee.1 Quite 90 per cent, of the Report is devoted to the manner of construction of these vessels, to the mode of testing them, to the evacuation of the envelopes, and to certain ancillary but vital problems, particularly those concerned with the behaviour of gas-adsorbents (activated charcoals, colloidal silica, etc.) at liquid-air temperature. Though the general reader may regret the absence from the Report of information” respecting both the manufacture of oxygen and the specific uses to which the liquid is put, the Committee has decided wisely in limiting its survey to the aspect of its subject which its members have experimentally studied.