in husbandry, a disease incident to plants, which affects them variously, the whole plant sometimes perishing by it, and sometimes only the leaves and and blossoms, which will be scorched and shrivelled up, the rest remaining green and flourishing.

Some have supposed that blights are usually produced by an easterly wind, which brings vast quantities of insects along with it, from some distant place, that, being lodged upon the surface of the leaves and flowers of fruit-trees, cause them to shrivel up and perish.

To cure this distemper, they advise the burning of wet litter on the windward side of the plants, that the smoke thereof may be carried to them by the wind, which they suppose will stifle and destroy the insects, and thereby cure the distemper.

Others direct the use of tobacco-dust, or to wash the trees with water wherein tobacco-stalks have been infused for twelve hours; which they say will destroy those insects, and recover the plants.

Pepper-dust scattered over the blossoms of fruit-trees, &c. has been recommended as very useful in this case; and there are some that advise the pulling off the leaves that are discoloured.

The true cause of blights seems to be continued dry easterly winds for several days together, without the intervention of showers, or any morning dew, by which the perspiration in the tender blossom is stopped; and if it so happens, that there is a long continuance of the same weather, it equally affects the tender leaves, whereby their colour is changed, and they wither and decay.

The best remedy for this distemper, is gently to wash and sprinkle over the tree, &c. from time to time with common water; and if the young shoots seem to be much infected, let them be washed with a woollen cloth, so as to clear them, if possible, from this glutinous matter, that their respiration and perspiration may not be obstructed. This operation ought to be performed early in the day, that the moisture may be exhaled before the cold of the night comes on: Nor should it be done when the sun shines very hot.

Another cause of blights in the spring, is sharp hoary frosts, which are often succeeded by hot sunshine in the daytime: This is the most sudden and certain destroyer of the fruits that is known.

**BLIGHTED corn.** See **Smut.**

**BLIND.** See **Blindness.**

**Pore-Blind,** or **pur-Blind.** A person who is very short-sighted is said to be pur-blind.

**Moon-Blind,** denotes horses that lose their sight at certain times of the moon.

**Blind** is also used figuratively, for things without apertures; Thus we say, a blind wall, a blind alembic, &c.

**Blind,** among traders, a kind of false light which they have in their warehouses and shops, to prevent too great a light from diminishing the lustre of their stuffs.

**Blind,** **Blinde,** or **Blend.** See **Blend.**

**BLINDS,** or **Blindes,** in the art of war, a sort of defence commonly made of oziers, or branches interwoven, and laid across between two rows of stakes, about the height of a man, and four or five feet asunder, used particularly at the heads of trenches, when they are extended in front towards the glacis; serving to shelter the workmen, and prevent their being overlooked by the enemy.

**Vol. I. Numb. 24.**

**BLINDNESS,** a total privation of sight, arising from an obstruction of the functions of the organs of sight, or from an entire deprivation of them. See **Medicine,** Of the **gutta serena,** &c.

**Blindness,** in farriery. When a horse becomes blind, it may be thus discerned: His walk or step is always uncertain and unequal, so that he does not set down his feet boldly when led in one's hand: But if the same horse be mounted by an expert horseman, and if he be a beast of metal, then the fear of the spurs will make him go resolutely and freely; so that his blindness can hardly be perceived.

**BLISTER,** in medicine, a thin bladder containing a watery humour, whether occasioned by burns, and the like accidents, or by vesicatories applied to different parts of the body for that purpose.

Cantharides, or Spanish flies, applied in the form of a plaster, are chiefly used with this intention. See **CANTHARIDES.**

**BLITE,** in botany. See **BLITUM.**

**BLITH,** a market-town in Nottinghamshire, about 18 miles north-west of Newark; in 5° W. long. and 53° 25' N. lat.

**BLITUM,** in botany, a genus of the monandria digynia clas. The calyx consists of three segments; there are no petals; and the seed, which is single, is inclosed in the calyx, which becomes a kind of berry. The species are two; viz. the capitatum, a native of Tyrol; and the virgatum, a native of Tartary and Spain.

**BLOATING,** among physicians. See **EMPHYSEMA.**

**BLOCK,** a large mass of wood, serving to work or cut things on.

**Blocks,** on ship-board, is the usual name of what we call pulleys at land. They are thick pieces of wood, some with three, four, or five shivers in them, through which all the running ropes run. Blocks, whether single or double, are distinguished and called by the names of the ropes they carry, and the uses they serve for.

Double blocks are used when there is occasion for much strength, because they will purchase with more ease than single blocks, though much slower.

Block and block is a phrase signifying that two blocks meet, in halting any tackle, or halliard, having such blocks belonging to them.

Fifth-block is hung in at a notch at the end of the davit. It serves to hale up the flooks of the anchor at the ship's prow.

Snatch-block is a great block with a shiver in it, and a notch cut through one of its cheeks, for the more ready receiving of any rope; as by this notch the middle-part of a rope may be reeved into the block, without passing it endwise. It is commonly fastened with a strap about the main-mast, close to the upper deck, and is chiefly used for the fall of the winding tackle, which is reeved into this block, and then brought to the captain.

**Block,** among bowlers, denotes the small bowl used as a mark.

**Block,** in falconry, the perch upon which they place the hawk. It ought to be covered with cloth.

**BLOCKADE,** in the art of war, the blocking up a place, place; by posting troops at all the avenues leading to it, to keep supplies of men and provisions from getting into it; and by these means propelling to starve it out, without making any regular attacks.

To raise a blockade, is to force the troops that keep the place blocked up, from their posts.