THE PROGRESS OE SCIENCE. 



287 



water in the aquaria can be kept at 

 any desired temperature throughout 

 the year. This will give an oppor- 

 tunity, not only for keeping alive a 

 number of different kinds of animals 

 that will not live at ordinary tempera- 

 tures, but will also give to the investi- 

 gator a chance to carry out important 

 researches on the effect of different 

 temperatures on marine forms. 



The addition to the station will 

 double its working capacity, since the 

 new part will be entirely devoted to 

 investigation, while in the two older 

 buildings there are the public aquaria, 

 the collecting department, and the 

 library. Zoology, botany physiology, 



gard to solutions. If we drop a lump 

 of sugar into a glass of water, the 

 sugar disappears and we have in the 

 tumbler a colorless liquid which looks 

 like water, but which has a different 

 taste. We are all agreed as to the 

 fact, but there has always been a dif- 

 ference of opinion as to what became 

 of the sugar. One view is that the 

 sugar and water are still there, but so 

 finely divided that we do not see the 

 sugar. If we grind a little dry sug*r 

 together with a good deal of charcoal, 

 we get a black mixture in which the 

 eye does not detect the sugar though 

 the sugar is unqestionably there. An- 

 other view is that we have neither 



r^ivfflltrtttflti* 





m 



The Proposed Enlargement of the Naples Station. 



physiological-chemistry and psychology 

 will benefit the world over by this en- 

 largement of the Naples Station. Pro- 

 fessor Dohrn deserves to be heartily 

 congratulated that his labors have 

 been crowned by success. May the time 

 come before long when the station will 

 be made symmetrical by the addition 

 of a fourth building! 



ARE SOLUTIONS MECHANICAL 

 MIXTURES OR NEW SUB- 

 STANCES? 

 In a recent volume Duhem sketches 

 the development of our ideas in re- 



water nor sugar in the tumbler, but a 

 new substance having properties dif- 

 fering more or less completely from 

 those of the sugar and water. This is 

 the view that we take in regard to 

 sugar itself when we speak of it as 

 made up of charcoal and water. The 

 first view, of a mechanical mixture, 

 was held by the Greek atomistic philo- 

 sophers under Epicurus while the sec- 

 ond view was defended by Aristotle and 

 the peripatetic philosophers. Through 

 the Middle Ages, the views of Aristotle 

 prevailed; but Bacon and Descartes 

 i brought the atomistic view to the front 



