gg" Sketch of the latest Improvements [Jan. 



experiments on this subject. I perused them with pleasure, because 

 1 found them very similar to a set of experiments which 1 made 

 myself on tlie sanre subject ten years ago, part of which w^ere 

 published in Nicholson's Journal, and part in a Report on Malting, 

 Brewing, and Distilling, printed by order of the House of Com- 

 mons ; but as this Report can scarcely be said to be published, as it 

 was never on sale, the facts contained in it have never become 

 generally known. 



Diibereiner found that when starch was roasted till its colour 

 becat?ie grey, it was only partially soluble in cold water, and the 

 solution was nearly colourless; but when roasted till it became 

 yellow, it dissolved completely in cold water, and the solution was 

 dark coloured. Both these solutions exhibited the same properties 

 when examined by re-agents. 



They were precipitated by alcohol. Infusion of nutgalls pro- 

 duced a copious precipitate, which was readily dissolved on heating 

 the liquid, and appeared again when the liquid cooled. Barytes 

 water likewise occasioned a precipitate, which v\as completely 

 soluble in acetic acid. It was precipitated also by nitrate of mer- 

 cury ; but not by silicated potash, permuriate of iron, nitrate of 

 silver, or corrosive sublimate ; nor by nitrate of lead, hydro-sul- 

 phuret of potash, or alum. It slowly decomposes nitric acid. 

 When treated with very dilute sulphuric acid, it is not converted 

 into sugar. It does not readily ferment. 



Dtibereiner likewise made observations on the quantity of starch 

 still to be found in beer ; on the difference between the starch of 

 raw grain and of malt. I have not room here to state the parti- 

 culars ; but know from previous experience that the facts which he 

 states are tolerably accurate. 



y. Cucumber. — Dr. John has subjected the cucumber to a che- 

 mical analysis. Tiie following were the constituents which he pro- 

 cured from 600 grains of it : — 



Water 582-80 



Matter similar to the fungin of mushrooms . . 3*20 



Albumen 0-80 



Resin 0-25 



Extractive with a sweet substance . ^ ...... . 9'y5 



Gluten 



Phospiiate of lime 



Phospliate of potash 



Phosplioric acid 



A salt with base of ammonia 'f- 3*00 



Malic acid united to a base 



Sulphate of potash 



Muriate of potash 



Phosphate of iron , 



Aromct . . . . , ~ 



^00-00 



