40 Kansas Academy of Science. 



cultivation. The true scientist does not seek to replace that 

 which is good, but to make something of service which has 

 not been known or utilized before, as may be seen in many 

 waste products turned into beautiful and useful materials by 

 the magic touch of the chemist. Many barren lands are made 

 to teem, as a great garden, with products to supply a nation's 

 needs, by the skill of the engineer and botanist. 



However, let us bear in mind that we have only made a 

 good beginning; that while the past century abounds with 

 brilliant results, the future should grow with increased ac- 

 celeration; that the facts which are being gathered and re- 

 corded will, in the centuries to come, be touched by some 

 genius and thus made to find a place of usefulness. One of 

 the things to be accomplished by the twentieth century, evi- 

 dently partly realized, is to effectually warn man of the danger 

 of setting any limit to knowledge. When we compare our 

 present with a century ago, and seek for the causes of the 

 great advancement in all our industrial arts, and observe the 

 new and ever widening fields of work, we may get some idea 

 of what the scientists have accomplished. 



We may consider some of the important things to be 

 achieved, along with some of the problems yet to be solved. 

 Many of these are of an accumulative character, and broaden 

 as new facts and uses are found. Examples may be given in 

 the changing from a mere hypothesis of one or two of our ad- 

 vanced thinkers to the generally accepted explanation of the 

 many very familiar conceptions of to-day, such as the great 

 age of the earth, the immateriality of heat, the electro-mag- 

 netic theory of light, the conservation of energy, and organic 

 evolution. The history of these is sufficient to show how a 

 truth gleaned from facts will widen in its applications and 

 be modified by new facts as it grows. 



The way in which scientific discoveries are often made may 

 be illustrated by the discovery of the planet Uranus. The 

 little difference found in the orbit of Neptune, from its cal- 

 culated orbit at a certain time, enabled the pencil of the 

 mathematician to point within a single degree of the very 

 spot where the planet was found. A similar phenomena ena- 

 bled Roemer to obtain the velocity of light. One of Jupiter's 

 moons eclipsed a few minutes before, and again a few minutes 

 after its calculated time. This difference, small though it 

 was, enabled the astronomer to show by his calculations that 



