Chemical Division. 



The Determination of Sugar in the Tomato. 



Tills determination requires some special precautions; the possi- 

 ble action of the organic acids present on polarized light, precludes 

 the use of the polariscope, and the possible action of other reduc- 

 ing substances than sugar on the Fehling solution, is liable to 

 render the results by this method too high. 



These possibilitieis may perhaps account for the different results 

 obtained by different analysts on the sugar in this fniit, although 

 it is true that there may be wide variations in the actual pi-opor- 

 tion of sugar in different varieties. 



In the report of the Maryland Experiment Station for 1889, page 

 07, are the resailts of the determinations of sugar in sixty-five 

 varieties, the percentage ranging from 1,76 to 3,52; one variety 

 gave 7.00 per cent. The detenninations were made in the aque- 

 ous extract directly, with Fehling's solution, used according to 

 the volumetric method. In the report of this station for 1891, 

 from 3.89 to 5.12 per cent of sugar is reported, as obtained by H. 

 Snyder on eight samples; in these determinations the extract was 

 examined by the polariscope. Two analyses by Italian chemists 

 gave, respectively, 1.74 and 3.7 per cent. 



In the case of nearly half of the analyses made at the Mary- 

 land Experiment Station the sum of the percentages of ash, sugar 

 and malic acid exceeds the total per cent of dry substance; it is 

 thus indicated that some of these determinations of the constitu- 

 ents of the dry substance are too high; and as other substances 

 besides these three are in all probability present in this dry sub- 

 stance, the error is eveti greater than thus indicated. 



Some study has been devoted to the method of determining 

 sugar in this fruit, and the matter is stni under investigation. The 

 following is given as a preHmiiiary report only. 



