ALOE, or ALOES, in pharmacy, the in spissated juice of the aloe perfoliata, asi atic aloe, prepared in the following man ner: from the leaves, fresh pulled, is pressed a juice, the thinner and purer part of which is poured ofd; and set in the sun to evaporate to a hard yellowish sub stance, which is called ruccotrine aloe, as being chiefly made at Succotra. The thicker part, being put into another ves sel, hardens into a. substance of a liver colour, and thence called aloe hepatica. The thickest part, or sediment, hardens into a coarse substance, called aloe ca. balina, or the horse-aloe, as being chiefly used as a purge for horses.
Fabroni has discovered that the recent juice of the leaves ofthealoe has the pro perty of absorbing oxygen, of assuminga fine reddish purple, and of yielding a pig ment which he strongly recommends to the artist.
ALOPECURUS,fax-tall-grars, in bo tany, a genus of the Triandria Digynia class of plants, and of the natural order of Grasses, the calyx of which is a bivalve glume, containing a single flower; the valves are hollow, of an ovate lanceolated figure, equal in size, and compressed ; the corolla is univalve ; the valve is con cave, and of the length of the clip, and has a very long arista inserted into its back near the base. There is no peri carpium the corolla itself remains, and contains the seed, which is single and of a roundish figure. There are 12 species.
The A.pratcnsis, meadow foxtail, is a na tive of most parts of Ehrope, and is found with us very common in pastures and meadows. It is'perennial, and flowers in May. This isthe best grass to be sown in low meadow ground.s, or in boggy places which have been drained. It is grateful to cattle, and possesses the three great requisities of quantity, quality, and earliness in a degree superior to any other, an'd is therefore highly deserving of cultivation in lands that are proper for it. The seed may be easily collected, ag it does not quit the chaff, and the spikes are very prtflific ; but the larvw of a spe cies of musew, which arc themsekes the prev of the annex campestris, devour the seeas so much, that in many- spikes scarce ly one is found perfect. A. agrestis is a very troublesome weed in cultivated ground, and among wheat it is execrated by farmers, under the name of blackbent; it is also common by vs:1y sides, as well as in corn fields, and in pastures in the Isle of Wight. It has acquired the name of mouse-tail grass in English, from the great 1 ength and slenderness of the spike, which resembles the tail of a mouse. It is annual, and flowers in July, continues flowering till autumn, and comes into bloom very soon after being sown.