27 



The change in the actual process of sugar making is absolutely revo- 

 lutionary. This is chiefly due to the supplanting of the iron kettle 

 for boiling the sap by the modern evaporator, an apparatus remark- 

 able for the ingenuity displayed in its construction and for its adapta- 

 bility to the needs of the industry. Evaporators are open pans 

 about 6 inches deep, 40 inches wide, and from 10 to 18 feet long. 

 They are often made with corrugated bottoms, to increase the heat- 

 ing surface. Partitions from side to side and open, at alternate ends 

 are placed in them at intervals of from 8 to 10 inches. (See fig. 8.) 

 The sap, whose flow from the storage tank is carefully regulated, 

 enters the evaporator at one end and flows slowly across the pan from 

 side to side, around the partitions, until it reaches the far end. By 

 that time it is reduced to the desired density. 



The rate of sap flow into the evaporator is of the utmost impor- 

 tance. All of the latest models have automatic regulators, by which 

 the inflow of sap increases or diminishes with the heat under the pan, 

 and the sap is entirely cut off when the fire gets low. With such an 

 arrangement no scorching of the sap is possible unless the supply tank 

 becomes empty. 



Improvements in the method of firing have kept pace with those in 

 boiling. From the old, rough fire box has been evolved the modern 

 portable arch, made of iron, with a flue running beneath the evap- 

 orator. It is lined with fire "brick, and has grate bars and accurate 

 dampers, so that the heat is more regular, while no smoke is allowed 

 to escape. Its economy of fuel is many times greater than that of the 

 old fire box. (Fig. 9.) 



The sugarhouse has advanced with other improvements and in 

 well-ordered groves to-day it is a neat, well-built affair, with two 

 rooms and a woodshed. The utmost cleanliness is insisted on and 

 maintained. 



It must not be supposed that the adoption of these improved meth- 

 ods has been universal. They are practicable chiefly for large opera- 

 tions. There are still many parts of the country in which sugar is 

 produced only in a small way, or for home use, and almost every 

 form of sugar making, even the primitive, may yet be found. But in 

 the great producing centers of the North Atlantic and Lake regions, 

 which mainly supply the market, improved methods are almost uni- 

 versally practiced. 



THE SAP SEASON. 



The sap season throughout the maple-sugar belt of the United 

 States generally begins about the middle of March and continues until 

 the third week in April, but it varies very widely with a late or an 

 early spring. Sugar making has begun as early as February 22 and as 



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