THE EEASON WHY. 215 



" And God said, Let us make man in our own image, after our likeness ; and let 

 them have dominion over the flsb of the sea, and over the fowl of the air, and 

 over the cattle, and over all the earth, and over every creeping thing." GEN. I. 



Because the blood coagulates over the cut, and throws out a kind 

 of lymph, which forms an incipient flesh, and excludes the air while 

 the blood-vessels are engaged in repairing the part. 



903. Why, since all the substance of the lody undergoes 

 change, do we preserve the same features throughout our 

 lives ? 



Because our substance changes in the minutest atoms ; and each 

 separate atom has a life of itself, the maintenance of which pre- 

 serves the unity and permanence of the whole. 



904. Why do moles upon the skin continue permanent, 

 while bruises and wounds disappear ? 



Because moles are themselves organised formations, and repair 

 themselves just as any other part of the body does. But bruises 

 and wounds are the result of accidental disturbances, which in course 

 of time become removed. 



905. Why do the marks of deep cuts sometimes remain? 

 If the cut is so deep and serious as to destroy the system of 



vessels which supply and repair the part, then it is evident that they 

 cannot work so perfectly as when in their sound condition. Their 

 functions are, therefore, interfered with, and instead of having 

 flesh uniform with the other parts of the system; there results a 

 tear, or a wound imperfectly repaired. 



906. Why when we hold our hands against a candle- 

 light do we perceive a beautiful crimson colour ? 



Because the fluids and vessels of the body are in some degree 

 transparent, and the thin textures of the sides of the fingers allows 

 the light to pass, and shows the beautiful crimson colour of the 

 blood. 



If the web of a frog's foot be brought iu the field of a good microscope, and 

 .set against a strong light, the blood may be seen in circulation, with the most 

 wonderful effect. Each vessel, and every globule of blood, can be seen most 

 distinctly, and the junction of the arteries and veins can be clearly traced. The 

 little boats of nutrition may be seen chasing each other in rapid succession, 

 and when the animal exerts itself to escape, the flow of the blood increases ; and 

 not unfrequently, under these circumstances of agitation, have we seen 

 two or three blood discs struggling together to enter a vessel that was too 

 small for them. Again and again they have endeavoured to find a passage, until 

 one of them happening to slip forward, got away, followed by the others 1 



