DISCUSSION OF MANUFACTURING DATA. 



57 



Summarizing the results from the investigation on this point it 

 appears that the usage is as follows: 



Use of cleansing agents in the various States. 



About 27 per cent of the total number of makers interviewed were 

 using cleansing agents, and nearly half of these were in New York, 

 about a quarter in Ohio, and one-eighth in Michigan. Only 18 per 

 cent of the Ohio makers were using cleansers, according to these 

 figures, 60 per cent of the New York makers, and 52 per cent of those 

 in Michigan. 



Among the 227 makers not using these agents the procedure gen- 

 erally adopted was to strain the product as often as possible. The 

 strainer in most cases was a heavy felt cloth to remove the very fine 

 material, and linen or flannel to remove the coarse sediment. Some 

 makers strain as many as six times before the sirup is finished, from 

 the bucket into the collecting tank, from this tank to the storage tank, 

 and sometimes again on its way to the evaporator; then the thin sirup 

 is strained, also the thick sirup, and a final straining is given as the 

 finished product goes into the cans. Undoubtedly the oftener the 

 product is strained the better its appearance and taste. The scum 

 as it comes to the top in boiling should be carefully removed with a 

 flat scoop. Removing the fine sediment or malate by continuous, 

 careful skimming, and settling will yield a bright, clear sirup. The 

 skimmings from sirup manufacture are used for various purposes. 

 Some make vinegar from them and some introduce the clear super- 

 natant liquid, after long settling, into the fresh sap, but those who 

 make maple sugar at the same camp generally turn them into sugar. 



Many makers use acid such as muriatic acid (hydrochloric) or 

 vinegar to remove the scale that has collected on the sides and bot- 

 tom of the evaporators, some scrape it off, and others reverse the 

 course of the sap. The scale being principally a lime salt is easily 

 dissolved by any weak acid, but the greatest care must be taken to 

 remove every trace of the acid used for this purpose from the evapo- 



