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It should also be remarked that beet-sugar, as will be seen by the analyses of various samples, contains very little invert-sugar, so little indeed that it is disregarded on the Continent.

The following table exhibits the specific rotatory power of commercial sugars, with the amount of cane-sugar calculated directly therefrom, and also the quantities of invert-sugar, ash, and moisture :

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If the formula (3) given above be applied to these results, the proportion of cane-sugar indicated will be from 1 to 2 per cent. more than the amount calculated directly from the angle of rotation.

It is sometimes useful to determine the approximate value of a sugar from the specific gravity of its aqueous solution; and for this purpose the following table, which shows the specific gravities of solutions containing from 1 to 66 per cent. by weight of pure cane-sugar, has been prepared :

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I

66 65

2

34 35 36 37

64

63

3 4 5 6

99 98 97 96 95 94 93 92 91

62

7 8 9 IO

39 40 41 42

1149-31 1154.28 1159'28 116432 1169:40 1174-51 1179066 1184.83 1190'05 1195-31 1200.60 1205.93 1211-29 121669 1222'14

90

II

44 45

12

89 88 87 86 85

61 60 59 58 57 56 55 54 53 52 51 50 49

47

48

1227.61

1003.89 1007.82 IOII°77 1015*75 1019*76 1023*79 1027.84 1031'93 1036'06 1040-21 1044'39 104861 105286 1057'13 1061'44 1065978 1070*14 1074'54 107897 1083.43 108793 1092-45 1097'01 110160 1106-22 II 10:87 1115.56 1120*28 1125'04 1129-83 113464 1139-50 114439

13 14 15 16 17 18 19 20

1233'13 1238.69

48

1244'28

47

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49 50 51 52 53 54 55 56 57 58 59 60 61

23

24 25 26 27 28 29

45 44 43 42 41 40 39 38 37 36 35 34

74 73 72 71 70 69 68 67

1249-92 1255-59 1261 630 1267'04 1272.83 127865 1284.51 1290-42 1296-35 1302-33 1308-35 1314-40 1320-50 132664

62

30

63

64

31 32 33

65 66

1

ADULTERATION.

Owing probably to the low price of cane-sugar, and to the difficulty of finding a suitable cheap adulterant, it is remarkably free from sophistication. If glucose or starch sugar were suspected to have been added, the quantity present might be estimated by Fehling's test, or by the polariscope, according to the methods previously described.

Perhaps the most serious deceit now practised upon the consumer of sugar is the sale of the lower products of the refiner as raw sugar. These products, technically known as “pieces," are caused to crystallize in very small crystals, and thus to hold a comparatively large percentage of water as well as of invert-sugar. They possess much less sweetening power than raw sugar, but having generally less colour are erroneously supposed by the public to combine cheapness with superiority of quality.

HONEY

HONEY, as is well known, is the saccharine substance collected by bees from the nectaries of flowers, and stored by them in combs for winter use. It consists, as might be expected from its origin; of a mixture of various bodies, the principal of which are dextroglucose, lævoglucose, and a third body, which is probably one of the less known sugars. Besides these there are small proportions of wax, gum, pollen, and other vegetable and some mineral matters.

The odour and flavour of honey vary according to the nature of the plants from which it has been collected. When new, it flows freely from the comb, and crystallizes after a time into a semi-solid mass. This change takes place to some extent in the comb if left for several months, and then heat and pressure are required for its removal. It is probable that the saccharine substances extracted from the flowers undergo modification in the honey-bag of the bees. In connection with this it has been obseryed that bees fed upon a solution of pure cane-sugar readily produce wax therefrom for the formation of the comb.

The third principal constituent referred to as probably one of the less known sugars is only partially fermentable, and has no direct action upon cupric tartrate, but is gradually converted into glucose when boiled for several hours with a few drops of sulphuric acid. Some chemists have represented this body as cane-sugar,

but when the samples of honey mentioned in the table below were boiled with sulphuric acid for a sufficient time to invert cane-sugar, the additional reduction of cupric tartrate corresponded to only 2'10 per cent. of cane-sugar in the honey from comb, and to less than 1 per cent in the other four samples. It is therefore evident that but a small part of it, if any, is canesugar, and we have therefore placed it in the table as "sugar not identified.” As honey is acid, and undergoes a slight fermentation, cane-sugar, even if originally present, would gradually be transformed into invert-sugar, and thus escape detection.

The following results have been obtained from an examination of five samples of commercial honey :

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The adulterants said to have been found in honey are gypsum, chalk, pipeclay, starch, glucose, and cane-sugar, but at the present day the three former are not likely to be used. Starch may be readily found by the microscope and solutions of iodine. Glucose cannot be detected by chemical means, and only by the polariscope when in sufficient quantity to change the angle of rotation beyond the limits found in genuine honey. Cane-sugаr may be found by the copper test, and also by the polariscope; and in this case the readings are taken both before and after inversion, the difference in the readings being proportionate to the amount of cane-sugar present.

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