MAPLE SUGAR. 30 
and 3.49, Indiana nearly 50 per cent of samples with a lead number 
between 3.50 and 3.74, and West Virginia no samples below 3.25. 
Ross ' indicates that the excess of both lead subacetate and sugar 
exert a marked effect upon the lead subacetate precipitate and shows 
that the effect of the excess of sugar is relatively greater. In the 
procedure for his method potassium sulphate is added to the solu- 
tion before the lead subacetate to overcome the solvent action of the 
sugar upon the lead precipitate. Ross believes this solvent action 
to be the cause of the lead number of mixtures of maple and cane 
sirup not being proportional to the percentage of maple present. 
The figures by Ross lead number given herein, however, apply only 
to sirups having a density of approximately 65 per cent solids which 
were made up from pure maple sugar, and the application of lead 
number determinations to mixtures of maple and cane sugar sirup 
has not been entered into in connection with this bulletin. In 
Table XIX the increase of the individual samples is grouped by 
differences of 0.10 and by States. 
TABLE XIX .—Dvifferences between Winton and Ross lead numbers. 
Number of samples. Per- 
cent- 
Lead number. 7 age of 
; : 2 sam- 
Ind. | Me. | Md. | Mass.} Mich.| N.H.| N. Y.| Ohio.) Pa. | Vt. Va. Total. ples. 
Winton higher than 
IEP ROSE Ge Bs SUH Ce ats Ss SS | a ree eee a PRI SL Ieee [ee Did ks eters ee ana ane I ese a 2 0.7 
Winton and Ross 
CC see Hos be sbselbeA se SSCepse St ee eee) eee ecaes| rans sibe| Ween ais (Paes [estes el Beet rs | eee 1 3 
Ross higher by less 
AIRE Ogee eee oe eet ecceis oie [areca Bars ota peicie o ote he csteiaee 1 3 re a 1 9 3.2 
Ross higher by more 
than: 
ONO soe A eee ag eee a Se alee hy Dera amy 2 Cn ees 1 10 3.6 
PAU SSAC cee ete ae oll tees ore MUN eee 3 1 Ea Rea me pe) 2 3 2 i 1 13 4.6 
1 LU we ae an | 2 1 Di eee 5 2 4 3 2 20 7.1 
AO Ee ol 2 1 1 1 A Ree Sm a a 11 1 8 8 1 34 12.2 
dott Sash os ee eel ee 2 3 2 See 10 1 8 0B hal eats 37 13.2 
LOO ase eis ates Suulhye icine a eisieies 2 yh 7 4 5 Giles 31 11.1 
MAR ene ses Mee lla | ee 2 6 3 5 4 4 1 Ts ee 40 14.3 
BR(Veeer oes sin 6 Bele ese 1 5 3 7 3 1 10 bees 37 13.2 
OO ee a tai: 2 1 1 1 3 CS ee ae 4 it 6 1 24 8.6 
WOOL = Sasa ea: 1 RY Sie ess [A 1 Dela 2 DN ERS Ss Re. ee 7 2.5 
LO sce e a esas = plssebae SSeaenl aes DS ees = 1 3 1 es 7 di Ween 8 2.9 
1D. OH Se ene See tae Fat ed pA | apes ik a Ps Atlee 1 eae PE OP | Le a OA ae 3 1.1 
HES (epee etre eye eye erties ie ed ah ea PE Cel is See 1 1 ea 1 By) eee Ieee 3 1.1 
EA Ras AeA Meer er ASS Spee Nee tL ete [eeeee-[eeeee eee sees MY | ake Se ee 1 .3 
Totaleeeas tot 19 4 11 14 23 12 54 31 43 62 7 280 | 100.0 
Difference: 
Average ...... 69 93 38 68 81 | 100 63 55 50 69 50) essscsl ae 
Maximum..... 112 126 92 116 104 133 137 121 142 129 O5 east eee 
Minimum..... 48 49 16 29 35 74 See ae. Saleeeee Cig Rega ele 
The increase varies greatly in the samples, the greatest increase 
being 1.42 and the least 0.15. Eighty per cent of the samples show 
an increase of from 0.30 to 1. Table XX gives the results of samples 
that show little difference between the two numbers, from which 
it is seen that factors other than the solubility of the lead precipitate 
in the sugar solution enter into the amount of the lead number. 
1U.S. Dept. Agr., Bur. Chem. Cir. 53. 
