Peoceedi^gs of the Polytechnic Associaiiox. 1063 



birds, and reptiles, and different animals, are but modifications of 

 the same kind. All these will be investigated bj the mici'oscope and 

 soon will doubtless shed much light on the development of animal 

 life. From a cell to a perfect animal the same law is followed. They 

 grow together, a partition is formed between them, and one develop- 

 ment after another is formed almost without limit. Prof. Agassiz 

 tells us that he has several specimens of animals he has not yet been 

 able to classify. . The impression given by the parent determines 

 how far the otispring shall go. Of the reptile it goes so far, but in 

 man it goes farther. In the lower organizations the more numerous 

 are the forms. This is the reason why in the lower forms there is 

 the greatest^ variety. There is another vegetable cell which is the 

 cause of fever and ague ; that cell which is developed in low grounds, 

 on a quiet day when there is no wind, and when the marshy grounds 

 have been dried. This cell will be lifted up in the air, and float over 

 the ground to some three or four feet, and when a person breathes 

 these cells a vegetable organization is generated, and the person will 

 have the fever. A strong wind will prevent this, and the heat of the 

 'Bun acts in the same way. This explains how persons who walk in 

 the evening on damp low ground will have the fever. A man whose 

 digestion is strong and eats hearty may go through this ground with- 

 out having the fever. Strong people do not get cancer, which is 

 another vegetable growth. Strong people do not have worms ; only 

 the weak ones, so we give them tonics to strengthen them. But it 

 is a useful rule not to expose ourselves when we do not feel. strong. 

 When we can fortify ourselves and feel vigorous vya can do so without 

 danger. No doubt but very soon most contagious diseases will be 

 proved to have a malarious origin. Attached to the microscope 

 shown was the spectroscope of a compact form. The spectroscope is 

 an important adjunct to the microscope for the purpose here spoken 

 of. The spectroscope is nothing but an arrangement for showing the. 

 rainbow colors, but we find that between these colors we have dark 

 lines, and when we pass the light through blood, we have two dark 

 lines. These lines are called absorption lines. There are eight very 

 prominent dark lines in the spectroscope, called a, h, c, d, e,f, g, h.. 

 When a little blood is placed on glass and put in the spectroscope, it 

 is analyzed, and the two absorption lines are seen between e andy,. 

 and these are called the absorption lines of blood. Xo such lines., 

 will appear in any other substance. Every liquid will have its own., 

 peculiar lines. By applying the spectroscope to the microscope we- 



