288 On the Culture of the Beet 



layer is conical : various fea (hells are found in their natural ftate ; others evidently the produft 

 of feme more ancient hill being agatized. We alfo find culm, or the wafhings from fome ftra- 

 tum of coal in the north, and the alum fchiftus from Whitby, all blended and mixed in one 

 heterogeneous mafs. 



lam, Sir, 



Your mofl: obedient and very humble fervant, 

 Hull, yfug. 14, iigg. John Ajlderson, M.D. 



11. 



A circumjlantial Defcrlptlon of the Method of cultivating the fVhite Beet fRunkelriibe), in 

 order to obtain the greateji ^antity of Saccharine Matter, and to prepare it for the Manu- 

 faSlure of Sugar. By F. C. Achard, DireSfor of the Phyfical Clafs in the Royal Academy. 

 of Sciences. ( Concluded from />. 243.^ 



18. AN fupport of thefe two pofitions, deduced from my own experiments, I wifli to add a few 

 well-known fadts. With regard to the firft, it is notorious, that not only the tender roots- 

 of afparagus, as well as thofe of hops, liquorice, and cucumber, poflefs a fweet tafte fo long as 

 they are protected againft the influence of light by being covered with earth ; and that they 

 lofe it-as fopn as, by fprouting out from the ground, they are expofed to the light and its adlion: 

 in which cafe they acquire the peculiar Iharp and acid tafte of the plant. — In the fame man- 

 ner the uncovered part of the lower, cole-rape has a fharp tafte, in comparifon with thofe of 

 its parts which are covered by the foil. Carrots fown between hemp and poppies, if all other 

 circumftances, fuch as foil and manure»_be-alike, become always fweeter than thofe which are 

 cultivated on a foil not ihaded by other overhanging vegetables. 



19. Some may, perhaps, afcribe the decreafe of fweetnefs in the root-germs pufiiing ouc 

 from the earth to the accefs of air thus facilitated, and not to the matter of light. But to 

 refute this afl"ertion, I (hall only mention, that the air undoubtedly penetrates, in every in- 

 fbnce, through the uppermoft ftratum of the ground, unlefs the foil be thoroughly argilla- 

 ceous, and of courfe very compaft. To this I add the fail known to every gardener, that 

 alparagus coming forth from the ground and covered with uglafs, acquires, in a fhort time, a 

 green head, and changes its agreeable fweetnefs for a bitter tafte; juft as if it had not been 

 covered. But if the afparagus be covered with an opake veflel, fuch as a flower-pot, &c. it 

 continues white in its fubfequent growth, and retains all tts fweetnefs. By this it is fully 

 proved, that the agency of the matter of light, with an exclufion of the adion of air, is the 

 only caufe of the lofs of fweetnefs in afparagus. The heads of carrots, parfnips, beet-root, 

 and perhaps of all vegetable root, which are not covered with the earth, lofe the fweet tafte 

 naturally belonging to them. And hence the lower part of the root, on which the light cannot 



