152 



THE GUIDE TO NATURE 



This role may become fatal if the 

 metals are in contact with electrolytes 

 (water), as these accelerate enormous- 

 ly the transformation velocity. The 

 volume changes which generally accom- 

 pany these transformations may cause 

 the disintegration of the materials. 



Research in pure science has its 

 place in the world's work. It is not a 

 mere pastime for the dilettante, nor is 

 it an easy pursuit for the trained inves- 

 tigator. At the bottom of all of our 

 real progress lies what may be called 

 the scientific spirit. 



*"Those who have come to under- 

 stand what is meant by scientific proof 

 of an hypothesis have learned that even 

 the most fascinating theory may go 

 down into oblivion if it cannot meet 

 new facts." 



"Scientific training tends to exalt the 

 idea of knowledge attained. 



_ Few people outside of the scientific 

 circle can grasp the satisfaction felt by 

 an investigator, when he feels that his 

 work has opened up a new line of 

 thought. The ordinary man, looking 

 at the progress of chemistry, would be 

 apt to imagine that the synthesis of a 

 new dye, the production of a new ex- 

 plosive or the simplifying of some 

 metallurgical operation w^ould cause a 

 profound impression in the scientific 

 world. But such things can be pro- 

 duced by methods which are largely 



sive, is a sudden development, which 

 the ordinary man probably never hears 

 mentioned, something which the scien- 



FIG. 4. Sl'KI'ACfc: ()!<■ LEAD AFTER IMMER- 

 SION IN A SOLUTION LEAD ACETATE. 



tific mind sees will revolutionize more 

 than one field of inquiry, and bring a 

 flood of light to bear upon intricate 

 problems still awaiting solution. Ap- 

 plied science any one can understand, 

 as it comes into touch Avith his daily 

 experience ; but applied science is only 

 a superstructure built upon the solid 

 foundations which have been laid by 

 men who never sought to make a cash 

 transaction of their knowledge. Yet, 

 if it had not been for their labor, di- 

 vorced apparently from all practical 

 application, applied science would not 

 stand where is stands today. On the 

 one hand are the needs of humanity, 

 on the other lies the search for knowl- 

 edge ; the bridge between them is ap- 

 plied science. But unless the pursuit 

 of knowledge was going on, there 

 would be no bridge, for the acquire- 

 ment of knowledge must come before 

 its application." 



A new study of one of the Trypano- 

 somes of the common rat, made by two 

 British zoologists, adds an important 

 point to our knowledge of human infec- 

 FiG.^ 3. ^ SURFACE OF FRESHLY CAST LEAD, tious by way of rat flcas, such for ex- 

 applications of old principles of no ample as the bubonic plague. The flea 

 great scientific interest. What is much takes the infection from the rat by 

 more rare, and therefore more impres- biting. But the rat becomes infected 

 ^Chemistry and its Borderland. A. W. only by licking its own fur or by eating 



infected insects, not by the flea's bite. 



Stewart. 



