NOTEMBEE 22, 1907] 



SCIENCE 



709 



chemistry— they carried away an inspira- 

 tion for research and an enthusiasm for 

 the laboratory method of instruction. 

 Largely from that laboratory as a center, 

 chemical laboratories for the training of 

 students spread throughout Germany and 

 the world. 



The fundamental principle of laboratory 

 instruction is that the student comes iato 

 direct personal contact with the things 

 about which he is to study and so gains 

 first-hand knowledge. While chemists were 

 the pioneers in this method of instruction, 

 physicists and biologists soon saw its ad- 

 vantages and introduced it in those sci- 

 ences. The principle has now permeated 

 almost every line of teaching and we hear, 

 to-day, of the laboratory method ia history 

 and psychology as well as in the physical 

 sciences. 



By the middle of the nineteenth century 

 the methods to be used in training a band 

 of chemists were being rapidly developed. 

 And it came to be more and more clearly 

 recognized that the training is not merely 

 to give to the student a knowledge of chem- 

 ical facts — it must give to him the power 

 to think for himself and to strike out into 

 new and untried paths. It is this power 

 of individual initiative which is given to 

 the students in the German laboratories 

 that has placed Germany in the front rank 

 in chemical manufacture as well as in re- 

 search and instruction. 



Some of the most important applications 

 of chemistry in the industries were devel- 

 oped early, along experimental lines having 

 little or no connection with scientific work. 

 One hundred and fifty years ago, those who 

 were smelting ores of iron and copper and 

 lead and zinc knew very little of the work 

 of the chemists of their day. And the 

 same was true of those who were tanning 

 leather, dyeing cottons, woolens and silks, 

 burning bricks and pottery and china, ma- 



king glass and working in many other 

 chemical industries already well developed. 

 The soda industry was one of the first 

 large chemical industries to be developed 

 on a scientific basis. When we consider 

 that the soda for our soap is now practi- 

 cally all made from salt, it seems hard to 

 believe that one hundred years ago soap 

 was made almost exclusively from the pot- 

 ash of wood ashes or from natural soda, the 

 supply of which was very limited. I think 

 we are forced to the conclusion that our 

 great-grandmothers used very much less 

 soap than we do. The first factory for 

 making soda from salt was built by Le 

 Blanc in Prance in 1791, but, partly be- 

 cause of the political conditions at the time 

 of the Revolution, partly for other reasons, 

 the factory was not a success. Le Blanc 

 himself died a few years later, in extreme 

 poverty, and it was not till 1823 that Mus- 

 pratt established the industry successfully 

 in England. Prom that time the Le Blanc 

 process held undisputed sway till the early 

 seventies. Since then it has fought a los- 

 ing battle with the ammonia soda process, 

 and to-day there is not a Le Blanc factory 

 to be found in America. Now the ammonia 

 soda is, in turn, being displaced rapidly by 

 electrolytic soda. This sort of competition 

 is typical of that which occurs in many 

 chemical manufactures. In the case of Le 

 Blanc soda it has been a most powerful 

 incentive toward the improvement of the 

 process. It has resulted in developing im- 

 proved mechanical appliances for carrying 

 out the operations, in the recovery of the 

 hydrochloric acid and its use in the manu- 

 facture of chloride of lime and in the re- 

 covery of sulphur from the calcium sul- 

 phide. I visited a Le Blanc factory in 

 England two years ago, where they told 

 me that their sulphur for making the sul- 

 phuric acid used in the process came from 

 Spain in the form of pyrites and that 85 



