5o Public Parks. 



mountains? Are not many of our rivered valleys not unadorned 

 witli woods — her braes beautiful with their birkin shaws ? And does 

 not stately ash, or sycamore, tower above the kirk-spire, in many a 

 quiet glen, overshadowing the humble house of God, the dial stone, 

 aged and green, and all the deep sunk, sinking, or upright array of 

 grave-stones, beneath which* 



'The rude forefathers of the hamlet sleep.' " 



LOCAL CONDITIONS. 



We now come to consider the local conditions by which we are 

 surrounded, both terrestial and atmospheric, in connection with their 

 influence upon man, particularly in causing disease. In these are 

 included the topography, nature of soil, temperature, winds, rains, 

 and humidity of the atmosphere, all being more or less intimately 

 connected, as there is no doubt that the surface controls the 

 atmosphere, as much as the atmosphere controls the surface. 



Chicago is situated in latitude 41" 52', longitude 78° 35', and is 

 591 feet above the level of the sea. The surface is nearly a flat level 

 and treeless plain, on the south-western shore of Lake Michigan. 

 The highest point above the level of the Lake for fifteen miles north, 

 is 38 feet,t and south-east for the same distance, 33 feet,J near the 

 Chicago University; from thence there is a gradual descent to the 

 Calumet, when the ground gradually rises. Directly south of the city 

 the surface is almost level, as the highest point in sixteen miles is 

 only 22 feet.§ The topography south-west is still more remarkable, 

 as for twenty miles, the highest point above the level of the lake is 

 at Summit, only 10 feet, where the waters of the St. Lawrence run 

 north-east. From the Summit there is a gradual descent, until the 

 ground is lower than the surface of the lake. At twenty miles 

 it is only i foot above the lake. || Three miles directly west, 

 the surface is 17 feet; five miles, 20 feet; seven miles, 27 

 feet ; at Austin, where no doubt was once the shore of the lake, 

 and continuing z\ miles farther at Hai'lem, we find an elevation 



* "Nodes Ambrosiance." 



t Milwaukee R. R. 



X City Engineer. 



§ Rock Island R. R. 



II Alton & St. Louis R. R. 



