116 REPORT OF THE COMMISSIONER OF AGRICULTURE. 



ivS palatable and wliolesome. Sucrose is usually inverted by heating 

 with an acid, and for commercial purposes sulphuric acid is the one gen- 

 erally employed. The difficulty of removing all traces of this acid ren- 

 ders the detection of inverted sugar somewhat easy by the presence of 

 the traces of the sulphuric acid which still remain in the solution. 'It is 

 now said, however, that inverted sugar is made in large quantities by 

 trcatujent with brewer's yeast and without the use of acids of any kind. 

 When added to honey in large quantities it can be detected by its great 

 hevo-roLatory power, which, however, decreases rapidly as the tempera- 

 ture rises. At 23° C. a pure invert sugar solution would mark — 32.5 

 divisions. In the present state of our knowledge it would be dilScult to 

 detect the addition of a small quantity of invert sugar to honey. From 

 the above studies it appears that pure honey is essentially composed of 

 invert sugar, together with a certain portion of sugars optically inactive 

 (anoptose), water, a small quantity of albuminous matter, ash, and solids 

 not sugar, i. c, those wJiich, while resembling sugar in chemical com- 

 l)Osition, are yet not detected in the ordinary process of analysis. 



In addition to the above it appears from the results of a large amount 

 of work done at my suggestion by Mr. G. L. Spencer, that pure honey 

 contains a varying amount of dextrine, which in cases amounts to as 

 much as 4 per cent.* 



This investigation is still in progress, and therefore its results cannot 

 be yet announced. The presence of dextrine in honey doubtless ac- 

 counts for the phenomenon that in some samples of pure honey the 

 Itevo-rotatory power is A^ery small, or according to some authors en- 

 tirely disappears, which would not be the case except for the presence 

 of some highly dextro-rotatory substance. 



ESTIMATION OF WATER IN GLUCOSES, HONEYS, ETC. 



The methods generally employed for the estimation of water in vis- 

 cous liquids are so well known that it will not be necessary to describe 

 them. Evaporation in Hat dishes, with or without stirring and drying 

 with gypsum or sand, are the processes most frequently employed. 



Any one who has practiced these methods need not be told how 

 troublesome and unsatisfactory the results are. Variations in the per- 

 centages of moisture obtained are always expected and are frequently 

 alarming. 



The following experiments have been tried to develop a method which 

 will give concordant, and therefore comparable, results. 



The success of the exi^eriments was largely due to the even system of 

 evaporation afforded by the steam-drying oven described below. 



This box contained three horizontal layers of IJ-inch copper tubing 

 placed at a vertical distance of 20 centimeters between them. This sys- 

 tem of steam pipes was inclosed in a box made of soapstone. Any non- 

 conducting material may be used for this box. Each layer of pipes is 

 connected with the steam service and with a trap. By this arrange- 

 ment all or any one of the sets of tubes can be furnished with steam. 

 The steam is admitted by an automatic valve by which the pressure of 

 tlie steam in the tubes of the box is constant, whatever the pressure 



* Since this iuvestigation was undertaken, Amthor (Rep. Anal. Clieni., 1885, p. 

 16o) Las shown that honey gathered from pine forests contains dextrine often in sucli 

 quantilioa as to become dextro-rotary. Klinger claims that this phenomenon is not 

 eschisivoly confined to honey of coniferous origin. According to our observations 

 even left-handed honey may contain marked quantities of dextrine. If this be so it 

 can hardly bo true, as'W. Lenz (Chem. Zeit., 8, Gi:3) aflirms, that after fermeututioa 

 honey yields no optically active substance. 



