CONTENTS. xix 



PAGE 



being the cause of Fire Boyle's experiments with Animals 

 under the Air-pump John Mayow, the greatest Chemist of the 

 Seventeenth Century His experiments upon the Air used in 

 Combustion Proves that the same portion is used in Respira- 

 tion Proves that Air which has lost its Fire-air is Lighter 

 Mayow's * Fire-air ' was Oxygen, and his Lighter Air Nitrogen 

 He traces out the effect which Fire-air produces in Animals 

 when Breathing -.,,*<. * .-"V .>'- .. :,--,; * I2 6 



CHAPTER XVII. 



SCIENCE OF THE SEVENTEENTH CENTURY (CONTINUED). 



Malpighi first uses the Microscope to examine Living Structures 

 He describes the Air-cells of the Lungs Watches the Cir- 

 culation of the Blood Observes the Malpighian Layer in the 

 Human Skin Describes the Structure of the Silkworm 

 Leeuwenhoeck discovers Animalcules Grew and Malpighi 

 discover the Cellular Structure of Plants The Stomates in 

 Leaves They study the Germination of Seeds Ray and 

 Willughby classify and describe Animals and Plants The 

 Friendship of these two Men . . . . 134 



CHAPTER XVIII. 

 SCIENCE OF THE SEVENTEENTH CENTURY (CONTINUED). 



1642, Birth of Newton His Education 1666, His three great 

 Discoveries first occur to him Method of Fluxions and Dif- 

 ferential Calculus First thought 'of the Theory of Gravitation 

 Failure of his Results in Consequence of the Faulty Measure- 

 ment of the size of the Earth 1682, Hears of Picart's new 

 Measurement Works out the result correctly, and proves the 

 Theory of Gravitation Explanation of this Theory Estab- 

 lishes the Law that Attraction varies inversely as the -squares 

 of the distance Explains the transmission of sound 1687, 

 Publishes the * Principia ' Some of the Problems dealt with"' 

 in this Work 144 



