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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 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 :

sugar not

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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.

APPENDIX.

TABLE I.

FOR CONVERTING DEGREES OF THE CENTIGRADE THERMOMETER INTO

DEGREES OF FAHRENHEIT'S SCALE.

Centigrade. Fahrenheit. || Centigrade. Fahrenheit.

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221° 230 239 248 257 266 275 284 293 302 311 320 329 338 347 356 365 374 383 392 401

165

131 140 149 158 167 176 185 194 203 212

170 175 180 185 190 195 200 205

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95 100

TABLE II.

COMPARISON OF FRENCH AND ENGLISH MEASURES OF WEIGHT.

Milligram Centigram Decigram Gram Decagram Hectogram Kilogram Myriagram

Grains.

o'015432 O'154323 I'543235 15432349 154'323488 1543'234880 15432'348800 154323488000

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honey 116
sugar 105

tea 5
Chicory

Elder leaf
Estimation of cane-sugar

glucose

34
· 106
• 106

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Fig

69

60
Cocoa

72
adulteration

88
analysis

82
botanical origin

72
chemical composition 76

.

• IOI

Glucose, manufacture of

estimation of

• 106

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willow

36

102

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-

Cocoa -

3

59

Sago

93
Sloe

38
Starch of arrowroot

92
potato

95
sago

93
tous les mois

95
Sugar

97
adulteration -

· 114
chemical composition 105
description
estimation

- 106
history -

· 103
origin

• 97
polariscopic examination 110

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· 98

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Maltose -
Mannitose

- 103
Mangold wurzel

61
Microscopic examination of

81
Microscopic examination of

coffee -
Microscopic examination of tea 32
Microscopic structure of acorn - 68

arrowroot 92

bean 64
carrot 63
chicory 60

81
coffee 46
date stone 70
elder leaf 35

fig 69
locust bear 65
mangold wurzel 61

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Cocoa.

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CA

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Tea

adulteration
analysis.
botanical origin
chemical composition
description
history
microscopic examination

structure
Tous les mois -
Turnip

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pea 65
potato 95

sago 93
sloe leaf 39
tea leaf 14

22

THE END.

CHARLES DICKENS AND EVANS, CRYSTAL PALACE PRESS.

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