EXPLANATION OF DIAGRAM II. 
A., B., and K. are dairy farms selling their product to retail milk 
dealer H. K. is the farm on which a case of scarlet fever occurred 
antedating the outbreak in Norwalk. 
The large square T. O. W. N. represents the city of Norwalk. 
H. is the retail milk dealer among whose customers all cases but two 
occurred. The dash-lines represent H.’s milk route, and each dot is a 
case of scarlet fever. 
C., T)., E., F., Gr., I.. and J. are other dairymen having routes in 
Norwalk. The lines extending from them into the city represent their 
milk routes and are introduced to show their freedom from the disease. 
( 30 ) 
