-33<5 On the Proclti^lon of Sugar, (sfc 



From thefe motives, I undertook a feries of experiments, two years and a half ago, when 

 I began my examination of the maple-fugar, the objciSl of which was to examine and corre£l 

 the experiments of former chemifts, as well as to extend our knowledge of the fubje6l. Of 

 ' thefe I {hall proceed to give an account. 



a. Experiments with India-corn, for the purpofe of making Sugar from it. 



The India corn [-zea mays) is dated by Juti*, to contain a very large quantity of true 

 fugar in the knobs of its young flalks. Mr. Jacquin f of Vienna is faid to have repeate'dly 

 fucceeded in preparing fugar from the ftalks of India-corn. The fame is aflerted by Ma- 

 rabelli J, in a treatife publiftied on this fubjeft. 



it is alfo reported, that the preparation of fugar from the ftalks of the India-corn, efpe- 

 cially when grown on a marfliy foil, has been attempted in the large way in Italy ; but that 

 the fugar obtained from them was ftill too dear, comparatively with the raw fugar from the 

 Weft Indies. 



As my chief end was to clear up this point by a£lual experiment, I made fome trials with 

 it, of which the following are the refults. 



In the fummer of 1796, I cultivated fome India-corn, on a moderately good, but fbme- 

 what fwampy foil. When the young plants were about fix inches high, their leaves, on 

 being chewed, had a tafte refembling that of liquorice, but the ftalks, efpecially near the 

 knots, had a faccharine tafte. The young plants were then cut ofF above ground, feparated 

 from the leaves and adhering impurities ; after which ten pounds of them were cut fmall, 

 then bruifed in a ftone mortar, and the juice prefled out. This liquor weighing five 

 pounds, and ftill pofleffing an herbaceous tafte, was clarified with whites of eggs, by which 

 means it became of a clear yellow colour like wine, and almoft entirely loft its difagreeable 

 tafte. This being reduced by boiling, afforded eight ounces of an agreeably flavoured ufe- 

 ful fyrup. 



b. Examination of the Ears of the India-corn. 



As the young ears of the India-corn poflefs a pleafing faccharine tafte, when fcarcely 

 formed, they were likewife fubjefted to inveftigation. Ten pounds, freed from all the fur^ 

 rounding leaves, were bruifed in a ftone mortar, and by preflure yielded four pounds of a 

 milky liquor, which could not be perfectly clarified by whites of eggs. By flow evapora- 

 tion to the confiftence of a fyrup, I obtained nine ounces of a brown pleafantly-tafted fyrup, 

 which, however, was diftinguiflied from the former by containing more mucilaginous matter. 



in eighteen places with an axe, and one of them was deprived of all its branches by lopping. Notwith- 

 ilanding this, both trees continued in a found ftate, and the very next fummer all their wounds healed up 

 of themfelves. It is otherwife with birch-trees, which always wither immediately after a ftrong draining; 

 The third objeftion is abfurd, and requires no refutation, becaufc contradiifted bycxperience. 



* See his Oekonomifche Schriften, part I, page 397, and part II, page 191. 



f Crell's Chemifche Annalen, for the year 1784, vol. I. page 96. 



} Franc. Marabelli de Zea Mays Planta analytica Difquifuio. Pavia 1793. 



c, Examinatiaa 



\A 



