14 THE MICROSCOPIST. 



organic creations. The large coal beds are the ruins of a 

 luxuriant and gigantic vegetation; and the vast limestone 

 rocks, which are so abundant on the earth's surface, are the 

 catacombs of myriads of animal tribes which are too minute 

 to be perceived by the unassisted vision. It exhibits, also, 

 that metallic ore, as the Bog Iron Ore, and immense layers of 

 earthy and rocky matter, are formed merely by the aggregation 

 of the skeletons or shields of Infusoria ; while beds of coral 

 rocks are still in the process of formation, the architects being 

 tiny marine polypi. Further, by this instrument, the nature 

 of gigantic fossil remains is often determined, and by it they 

 are assigned their true place in the classification of the 

 naturalist. 



To the student of vegetable physiology, the microscope is an 

 indispensable instrument. By it he is enabled to trace the 

 first beginnings of vegetable life, and the function of the dif- 

 ferent tissues and vessels in plants. 



The zoologist finds it also a necessary auxiliary. Without 

 it, not only would the structure and functions of many animals 

 remain unknown, but the existence of numerous species would 

 be undiscovered. 



It is to the medical student and practitioner, however, that 

 the microscope especially commends itself for its utility. A 

 new branch of medical study histology has been created by 

 its means alone ; while its contributions to morbid anatomy and 

 physiology, or pathology, are indispensable to the student or 

 physician who would excel, or even keep pace with the progress 

 of others, in his profession. To such the following remarks 

 will doubtless be interesting. 



Histology is that science which treats of the minute or ulti- 

 mate structure and composition of the different textures of 

 organized bodies. It is derived from itfros, a tissue or web, 

 and Xoyoc:, a discourse. 



