THE SUMMER HEAT OF CITIES. 441 



The difference between the mean temperature of the city at Cooper 

 Institute and at the Arsenal, Central Park, for a single month, illus- 

 trates this fact. Another striking difference between the tempera- 

 ture of these two points of observation is that the range is much 

 greater at Central Park than at Cooper Institute, the temperature 

 falling at night more at the former than at the latter place. The 

 effect of vegetation is to lower the temperature at night, while brick 

 and stone retain the heat and prevent any considerable fall of tem- 

 perature during the twenty-four hours. It may be said of ~New York 

 that it has all the conditions of increased temperature above given 

 in an intensified form. It has a southern exposure; all of its broad 

 avenues run north and south; the surface is covered with stone, brick, 

 and asphalt; it is destitute of vegetation except in its parks, which 

 have a very limited area compared with the needs of the city; its 

 buildings are irregularly arranged and crowded together so as to give 

 the largest amount of elevation with the least superficial area; ven- 

 tilation of courts, areas, and living rooms is sacrificed; its ill-con- 

 structed and overcrowded tenement houses, especially of certain dis- 

 tricts, have the largest population to surface area of any city in the 

 civilized world. To these natural and structural unfavorable sani- 

 tary conditions must be added the enormous production of artificial 

 heat in dwellings. When the summer temperature begins to rise 

 the solar heat is constantly added to the artificial heat already existing. 

 The temperature of the whole vast mass of stones, bricks, mortar, and 

 asphalt gradually increases, with no other mitigation or modification 

 than that caused by the inconstant winds and occasional rainstorms. 

 And the evils of high temperature are yearly increasing as the area 

 of brick, stone, and asphalt extends.. The records of sunstroke 

 during the past few years is appalling, both on account of the number 

 of cases and their comparative increase. If no adequate remedy is 

 discovered and applied, the day would not seem to be distant when 

 the resident, especially if he is a laborer, will remain in the city 

 and pursue his work during the summer at the constant risk of his 

 life. 



Turning now to consider the question of the measures which are 

 best adapted to protect the present and future population of New 

 York from the effects of high summer temperatures, we are met by 

 many suggestions of more or less value. The more important meth- 

 ods proposed are: a large supply of public baths; the daily flushing 

 of the streets with an immense volume of river water; recreation 

 piers; excursions to the seashore; temporary residence in the coun- 

 try, etc. But these are for the most part temporary expedients, ap- 

 plicable to individuals, and are but accessory to some more radical 

 measure which aims to so change the atmospheric conditions that ex- 



