194 EIGHTEENTH CENTURY. PT. in. 



those of animals, and he decomposed in a most beautiful 

 and simple manner milk, blood, bile, and those fluids called 

 chyle and lymph which convey nourishment to the blood. 

 These he compared with the sap, gums, resins, and oils of 

 plants, and showed that animal bodies are made up of 

 altered vegetable matter, just as plants are in their turn 

 composed of matter taken from the soil and the air ; and 

 he suggested that by careful experiments it would at last be 

 possible to discover exactly the materials of which all living, 

 beings were made. 



Boerhaave's analyses of organic substances were very 

 rough and imperfect compared to those which are made now ; 

 for you must remember that the' four gases, oxygen, hydro- 

 gen, nitrogen, and carbonic acid, which we now know are the 

 chief constituents of plants, were not yet discovered. Yet 

 even these rough attempts were so interesting that students 

 crowded round the doors of his lecture-room for hours 

 before the lecture began, to secure admission ; and there can 

 be no doubt that his ' Elements of Chemistry/ published in 

 .1732, contained the first steps in the study of the chemistry 

 (of living things. Boerhaave was also a celebrated botanist. 

 |He died in 1738, and deserves always to be remembered as 

 me of the greatest teachers of the eighteenth century. 



Chief Works consulted. Brewster's ' Encyclopaedia* ' Boerhaave ;' 

 Miller's 'Organic Chemistry,' 1869; Cuvier, 'Hist, des Sciences 

 Naturelles;' Sprengel, 'Hist, de la Medicine,' 1815; Burton's 'Life 

 and Writings of Boerhaave, ' 1 746 ; Boerhaave, ' Elements of 

 Chemistry,' Englished by Dallowe, 1735; Hales' 'Essays concerning 

 Vegetable Staticks,' 1759. 



