DISCUSSION OF CHEMICAL DATA. 59 



, 



decreased as the density falls. The flavor also enters into the valua- 

 tion of the sirup. 



A great many buyers classify all purchases under three grades 

 according to the following color scale: Grade Al or AA (color Nos. 6, 

 7, 8, and 9); Grade A (Nos. 10, 11, and 12); and Grade B (Nos. 13, 

 14, 15, and 16). 



In buying, some of the brokers require farmers to sign guaranties 

 worded somewhat as follows: "I hereby guarantee the maple sirup 

 sold you to-day to be absolutely pure ; made only from the sap of the 

 maple tree with no additions whatever except such as might be used 

 for cleansing." This is a comparatively recent procedure and may in 

 part be traced directly to the Food and Drugs Act. At the farmers' 

 camps visited very little adulteration was noted or even suspected. 

 If any suspicious facts were observed, the samples collected were 

 marked and the analytical results were not entered in the general 

 table. 



DISCUSSION OF PHYSICAL AND CHEMICAL DATA. 



COLOR. 



The color varies from that of a very light water-white to a very 

 irk reddish brown. On the scale mentioned on page 15 and pic- 

 tured in the illustration (PI. I) the colors vary from 4 (the lightest) to 

 16 (the darkest). Considered by States, the averages are for Indiana, 

 10+; Maine, 8+; Massachusetts, 7; Michigan, 8+; New Hamp- 

 shire, 8; New York, 7; Ohio, 8; Pennsylvania, 8; Vermont, 9; and 

 West Virginia, 9, giving an average for the United States of 8-f. 

 The plus sign after a figure means that the color was darker than the 

 number indicates but lighter than the next number. The data 

 recorded (p. 93) show that the middle run is about the same in color 

 as the first but the last runs are darker. 



Tabulating the results on color determinations by States and 

 grouping the samples in each State under the appropriate color num- 

 ber it is seen that in most cases the largest number of samples have a 

 color of 8 or 9, though there are exceptions. In the United States 

 76.8 per cent of the samples have a color lighter than No. 10, while 

 in Canada only 52.5 per cent possess these lighter colors, 31.2 per 

 cent of the Canadian samples having a color of Nos. 11 and 12, 

 while only 10.7 per cent are so classified in the United States. Of the 

 total 481 samples about 73 per cent have a color lighter than No. 10. 



