Page:Popular Science Monthly Volume 48.djvu/285

This page has been proofread, but needs to be validated.

the various training colleges which, instruct and examine and authorize, there are now sundry professional associations. Of a general kind come the Teachers' Guild and the Scottish Educational Institute. Then of more special kinds come the Head Masters [of Public Schools] Conference; the Association of Head Masters of Intermediate Secondary Schools; the Association of Head Mistresses; the College of Preceptors; the Association of Assistant Masters; the National Union of Teachers.

So, too, with the appliances for maintaining a general organization of all concerned in education—schoolmasters, assistants, colleges, and the various unions above named. This professorial class, like other professorial classes, has journals weekly and monthly, some general and some special, representing its interests, serving for communication among its members, and helping to consolidate it.


FROM the first chapter of the first book of Moses, called Genesis, we learn that, as between water and land, the ocean had the first place in terrestrial existence, for it is there stated that on the third day in the calendar of the creation the waters under the heavens were gathered together and the dry land appeared. Both from a chemical and a geological standpoint it appears that the waters of the ocean were salt from the beginning. Dr. T. S. Hunt, one of the ablest writers on the physical history of the globe, in his chemical and geological essays, referring to that period when the earth was in a molten state and surrounded by an envelope of gases and of vapor of water, states: "There would be the conversion of all the carbonates, chlorides, and sulphates into silicates, and the separation of carbon, chlorine, and sulphur in the form of acid gases which, with nitrogen, vapor of water, and a probable excess of oxygen, could form the dense primeval atmosphere. The resulting fused mass would contain all the bases as silicates, and must have resembled certain furnace slags or volcanic glasses. The atmosphere, charged with acid gases which surrounded this primitive rock, must have been of great density. Under the pressure of a high barometric column condensation could take place at a temperature much above the present boiling point of water, and the depressed portions of the half-cooled crust would be flooded with a highly heated solution of hydrochloric and sulphuric acids, whose action in decomposing the silicates can easily be understood. The formation of the chlorides and sulphates of the various bases, and the separation of