To determine the relative weight of the skins of barley and big, we made choice of three parcels of grain, all excellent in their kinds, namely, Norfolk barley, Haddington barley, and Lanark big. The weights of the whole grain, and of the cuticles of each of these, was as follows: we shall find almost all the grains nearly or a size ; though, in some cases, the grain constituting the upper termination of the spike is rather smaller than the rest.
These circumstances may strike the reader as too minute and trifling to be stated in such detail ; but we shall find afterwards, that they will furnish us with an explanation of some anomalous circumatan ces,that occur when these two species of hordeson are couverted into malt. The value of barley (or its produce in alcohol) is rather improved, while big, on the contrary, is deteriorated by malting it, at least 20 per cent.
The constituents of the kernel of barley and big, as far as we are able to ascertain at present, are the same. Barley has been subjected to an elaborate chemical analysis by Einhoft who obtained from 3840 parts of barley-corns the following consti tuents: From this we see, that there is little difference between the weight of the skin of Norfolk and Had dington barley, but a very considerable one between Haddington barley and Lanark big. Hence it would seem that this difference is not owing to the climate in which the barley vegetates, but rather to a differ, ence in the nature of the two species.
The bulks of these two species of grain to each nthPr_ IR AR fnlienvot These quantities represent the average bulk of a corn of each kind. Thus it appears that a grain of barley is rather more than *th part larger than a grain of big.
Finally, from a comparison of many thousand corns of each species with each other, it appears that the inequality between the size of different grains of big, is greater than between different grains of barley. Indeed, if we examine an ear of big, when nearly ripe, we shall perceive that the corns towards the bottom of the ear are smaller than those towards the summit and about the middle of the ear. Several of these bottom grains are usually abortive, or consist only of skin, but this is not al ways the case. In an ear of barley, on the contrary, The writer of this article has likewise extracted from barley, by means of alcohol, a small quantity of an oily matter, which has an asparagus green colour, and does not burn with the same readiness as an oil. It has very much the appearance of olive oil coagulated, but its consistence is less, and its colour is darker. It has little smell, and its taste resembles the flavour of spirits from raw grain. We have likewise found in big a quantity of nitrate of soda. Hence, it is likely, that this salt exists as a common constituent of barley. We obtained it by steeping big in water for two days, concentrating the liquid, and setting it aside in a dry place. Many rhomboidal crystals of nitrate of soda gradually make their appearance as the liquid evaporates.
We shall terminate this chapter by a TABLE, exhi biting the most remarkable properties of a consider able number of specimens of British barley and big, as determined by the writer of this article. The different specimens are distinguished by the name of the county in which they grew. By the bushel in the table is meant the Winchester bushel of 2150.42 cubic inches.