416 



Popular Science Monthly 



pioneer 



Maqnesium Tape 



The current then uses the path of vaporous 

 carbon as a conducting medium and heats it 

 to a great temperature. The greater the 

 current intensity used, the greater will be 

 the resulting heat produced. 



Making Diamonds at Home 



The furnace with which Moissan 

 user of the electric arc, 

 conducted startling ex- 

 periments and made 

 many discoveries, is 

 most simple. It con- 

 sists principally of an 

 arc drawn between two 

 large carbon electrodes 

 and supplied with a 

 very heavy current. 

 The arc is enclosed in 

 the cavity formed by two 

 large limestone blocks. In 

 this simple furnace Moissan 

 produced a temperature of 

 sixty-three hundred degrees 

 Fahrenheit and, had it not 

 been for the fact that carbon boils at this 

 temperature, we can not predict how much 

 further the temperature could have been 

 carried. 



With the aid of his electric furnace 

 Moissan made as many as one hundred and 

 fifty valuable contributions to science. 

 Among his more notable discoveries was the 

 production of the carbides of nearly every 

 metallic element and the artificial creation 

 of the diamond which is crystallized carbon. 



The science of electrothermics has de- 

 veloped many new industries and sub- 

 stances, not only through the efforts of 

 Professor Moissan, but many other inves- 

 tigators as well. 

 Nor have all 

 the industries 

 founded made 

 use of the arc in 

 their furnaces. 

 Many, such as 

 Acheson's for 

 the production 

 of carborundum 

 and graphite, 

 are of a differ- 

 ent type. In 

 Acheson's fur- 

 nace the sub- 

 stances to be 

 converted form 

 a part of an 

 electrical circuit 



Graphite Crucible 



The essential elements which 

 are used in preparing 

 thermit for the laboratory 



and offer such resistance that temperatures 

 as high as sixty-three hundred degrees 

 Fahrenheit have been produced. 



It was by means of the electric furnace 

 that Hall made aluminum a commercial 

 article. Before his time it was a laboratory 

 curiosity. Taylor produced carbon-disul- 

 phide and Willson developed a means of 

 producing calcium carbide on a commercial 

 scale. 

 Sodium Peroxide The highest temper- 

 ature ever reached by 

 man was produced a 

 few years ago by two English 

 experimenters, Sir Andrew 

 Noble and Sir F. Abel. This 

 was done by an explosive called 

 cordite, which is a form of 

 smokeless powder composed 

 chiefly of guncotton, nitro- 

 glycerine and mineral jelly. 

 When this was exploded in 

 a durable steel cylinder, a 

 temperature of ninety-four 

 hundred degrees Fahrenheit 

 was produced. This was due to the 

 suddenness of the reaction, and, although 

 of momentary duration, it was an interest- 

 ing scientific achievement nevertheless. 

 With the aid of cordite, Sir William 

 Crookes was able to make small diamonds. 



Using the intense heat of the electric arc in welding 

 street-car rails. Note the head gear worn by the man 



Doff Your Hat to the Goat— Its Milk 

 Saves Babies' Lives 



CHEMICAL studies made recently at the 

 Agricultural Experiment Station at 

 Geneva, N. Y., to ascertain the value of 

 goats' milk as a substitute for cows' milk 

 showed marked differences between the 

 two kinds of 

 milk but could 

 reveal no reason 

 why "Goats' 

 milk agrees bet- 

 ter with babies 

 than does cows' 

 milk," the fact 

 that it does so 

 being unques- 

 tioned. The 

 Station main- 

 tains a herd of 

 goats in order 

 that the inves- 

 tigations may 

 be carried out 

 under the best 

 conditions. 



