198 PROGRESS OF SCIENCE. 



{ III. GEOMETRY, subdivided into 



A. Elementary or Euclidian. 



B. Higher or Project! ve vel Descriptive. 



C. Analytical Geometry. 

 w 



a / 



IV. CONICS, or Curves of the Second Order : 



(a) Ellipse, (b) Parabola, (c) Hyperbola. 





V. MECHANICS : 



(a) Statics, (b} Dynamics, (c) Kinetics. 





VI. APPLIED MATHEMATICS : 



A. Mensuration, B. Hydrostatics, Dynamics, Mechanics, 

 C. Geodesy, D. Astronomy. 



Hence mathematics have been the chief instrument by 

 which the physical sciences have progressed; namely, 

 astronomy, gravity, hydrostatics, hydrodynamics, hydro- 

 mechanics, optics, heat, light, acoustics, magnetism, elec- 

 tricity, meteorology, geography, chemistry, engineering 

 (machinery and surveying), architecture, naval architecture 

 in fact all the phenomena relating to Force and Matter 

 to which may be added political economy, currency, banking,. 

 and insurance. Now, what we have to note and remember 

 is that each branch, so vastly has science extended its area, 

 admits, just as mathematics do, of several important sub- 

 divisions each of which is often extensive enough to engross 

 by itself a man's whole lifetime, each, too, employing an army 

 of earnest workers. 



GROUP V. ASTRONOMY. 



1592 1655. Gassendi was the first to observe, by means 

 of the camera obscura, MERCURY passing across the disk of 

 the sun (November 7, 1631) a phenomenon which recurs at 

 intervals of from seven to thirteen years. As a mathe- 

 matician and physicist, he wrote on the communication of 

 movement. 



161 1 87. Hevelius drew up, after careful observations of 

 the moon, the first SELENOGRAPHICAL MAPS ; increased the 

 catalogue of stars just after Galileo those in the Zodiac 

 especially ; was the first observer of the PHASES OF MERCURY, 



