218 



THE MICROSCOPE AND ITS LESSONS. 



I have already told you that in the human lungs there 

 are six hundred millions of air-cells. You shall now see 

 with your own eyes what these air-cells are, first in health, 

 and then in disease. Tell me, then, if we are not " fear- 

 fully and wonderfully made," and whether a house so 

 marvellously constructed should not have a tenant in 

 every respect worthy of its glorious Builder. 



Here, then, first, is a preparation of the human lung. 



The whole interior, 

 you perceive, is di- 

 vided into a multitude 

 of air - cells, which 

 freely communicate 

 with each other, and 

 with the ultimate 

 ramifications of the air- 

 tubes which the tra- 

 chea, that is, the wind- 

 pipe, subdivides ; and 

 the network of the 

 blood-vessels is so dis- 

 posed in the partitions between these almost countless 

 cavities, that the blood is exposed to the air on both sides. 

 Such is a very brief and very imperfect reference to 

 some few of the many wonders connected with our re- 

 spiratory organs in health. Now let us see what that 

 fatal disease called " consumption " looks like when seen 

 with our microscope. " Why," you say, " this looks for 

 all the world like a piece of mouldy flesh." That is, in 

 my opinion, exactly what it is. The air-cells in our 

 object are almost entirely destroyed by parasitic growth. 

 Had you seen the doctor's certificate which accompanied 

 the burial of the person from whose body this little bit of 

 diseased lung was taken, you would have read the Greek 



Air-cells of the human lung. 



