Page:Willich, A. F. M. - The Domestic Encyclopædia (Vol. 1, 1802).djvu/315

285&#93; BLI shoots have even been restored, by first whipping them, and then tying up a bunch of elder-leaves among them. A composition of oil and sul- phur, mixed to the consistence of paint, will also prove highly ad- vantageous, in expelling young in- serts from the trees infested by them. But the most effectual remedy is, to wash the plants gently and frequently with pure water, and if the young shoots be much infected, to rub them gently with a woollen cloth, in order to clear away the glutinous matter. This operation should be performed in the morn- ing, that the moisture may be ex- haled before night. It deserves tobe mentioned, that the blights most destructiveto fruit- trees, are those produced by the hoar frosts in spring mornings, which are often succeeded by warm sun-shine. Blighted Corn. See Smut. BLINDNESS, implies either a partial or total privation of sight, proceeding from some defect of the organs of vision, or an impaired state of their functions. Hence it may be either total, partial, tran- sient, periodical, or nocturnal. The causes of blindness are likewise va- rious, such as weakness, or decay of the optic nerves, preternatural confirmation of the organs, exter- nal violence, malignant effluvia, poisonous liquids dropt into the too frequent exposure to in- •.i, long confinement in dark places, 3cc. As we propose to treat of the principal diseases of the eye, under liif heads' of Cataract, Gu. ena, and Sight, We shall here that those lis wild are horn blind, BLI [iftj or lose their sight in infancy, sei- do a recover that hasp ulty, and ought therefore to be educated for such pursuits as a:c adequate to their individual capacities. It is, indeed, equally cruel, and in- consistent with good, polity, to surfer these pitiable beings fre- quently to spend a vagrant life, and remain in the darkest igno- rance. On the contrary, it has been uniformly observed, that the privation of one sense renders the others comparatively more acute and useful. Hence blind persons generally hear better, and possess a more accurate sense of touch, than those who enjoy all their sen- sitive faculties j and we have also many instances of the poetical and philosophical talents displayed bv the former. Widi a view to contribute our share towards alleviating the severe lot of such unfortunate individuals, we shall here communicate an in- vention of IIr. Thomas Gur.v- villi:, organist, of Hoss, in He- refordshire; who, in the year 17/0, received a premium of fif- teen guineas; and, in 1/65, for some additional improvements, the silver medal, from the Society for the Encouragement of Arts, !kc. It i-> ferriarfcable, that the ingenious inventor is _ himself deprived of sight ; and that by die use of his machine, any blind person may be taught the elements of arithme- tic, namely, addition, subtraction, multiplication, division^ reduction, and the rale of three, whether in fl weights, or measures of every kind, as perfectly as it may- be performed on paper. His appa- ratus being of a simple construc- tion, and so contrived that it may be of service in leaching the art 6i reckoning, to young children, in a very