B L A 



B L A 



rays that fall upon it ; but that white refleifls them. 

 This, adds the hiftorian of philofophy, is thefirft dillinft ac- 

 count I havemet with of this fenfibie hypothefis. Mr. Boyle 

 alfo made feveral obfervations and experiments, which dc- 

 nionftrate his theory in a very fatisfaftory manner. See 

 Black. 



Sir Ifaac Newton, in his Optics, flicw, that for the pro- 

 duftion of black colours, the corpufcles inuil be Icfs than 

 thofc which exhibit any other colours ; becaule, where the 

 fi/AS of the component particles are greater, there is too 

 much light reflefled to conftitute this colour : but, if they 

 be a little Icfs than is requifite to rcfleft the white and very 

 faint blue of the firft order, they will refleft fo little light, 

 as to appear inteulely black ; and yet may, perhaps, 

 refleft it varioully to and fro within them fo long, till 

 it happen to be itifled and loft ; by which means they 

 will appear black in all pofitions of the eye, without any 

 tranfparcncy. 



And hence it appears, why fire, and putrefaftion, by 

 dividing the particles of fubllances, turn them black : why 

 fmall quantities of black fubllanccs impart their colours very 

 freely, and intenfelv, to other fubftances, to which they are 

 applied ; the minute particles of thefe, by reafon of their 

 very great nun-ber, eafily overfpreading the grob particles 

 of others. Hence alfo appears, why glafs, ground very 

 elaborately with fand, on a copper plate, till it be v.'ell po- 

 lifhed, makes the fand, together with what by rubbing is 

 worn off from the glafs and copper, become very black ; 

 and why black fubftances do, foonell of all others, become 

 hot in thr lun's light, and burn (which ^ffcft may proceed 

 partly from the multitude of refractions in a little room, and 

 partly from the eafy commotion of fuch very Imall particles'! : 

 alfo why blacks are ufuallv a little inclined towat-ds a bluifh 

 colour ; for that they are fo, may be feen by illuminating 

 white ])aper with light reflefted from black iubilances, where 

 the paper will ufually appear of a bluith white; and the 

 realon is, that black borders on the obicure blue of the tirft 

 ordsr of colours ; and therefore reflcfts more rays of that 

 colour than any other. 



BLACKRIE, Alexander, in Biography, apothecary, 

 a native of Scotland, publifhed in 1766 a difquifition on 

 medicines that dlffulve the ftone, in which Dr. Chittick's 

 fecret is laid open, i2mo. It was reprinted in 1771, with 

 additions. Fie found the folvent to be the lixivium fapo- 

 narium, which may be given, he fays, advantai^eoufly, mixed 

 with lime-water, even when blood is voided with the urine. 

 When the bladder becomes ulcerated, wounded by the afpe- 

 rities of the ftone, he recommends the pareira brava and uva 

 urfi. When pain in the loins or pubes is violent, he gives 

 opium ; and he has known, he fays, perfons void ftones in 

 their fleep, while taking that drug. Perfons who void red 

 fend or gravel with their urine, are never affefted, he fays, 

 with the ftone. Haller. Bib. Chirurg. 



BLACKS, Negroes : a people, fo called from the colour 

 of their Jidn. For the reafon of their colour, and the com- 

 merce of them, fee Negro. 



Blacks, is alfo a name given to an alTociation ofdiforderly 

 and ill-defigning perfons, formerly herding chiefly about 

 Waltham in Eifex, who dellroyed deer, robbed tith-ponds, 

 ruined timber, &c. See Black aa. 



BLACKSOD Bay, in fome old maps erroneoufly called 

 Black harbour, in Geography, a large bay lying between the 

 peninfula of the Mullet, and the main land of the county of 

 Mayo, Ireland, to the fouth of the ifthmus. It is well 

 fheltered, the ground in moft parts clean, and fufBciently 

 deep for large (hips ; but the ground being a hard fand, it is 

 not thought that it will hold well in hard gales from the weft 

 and fouth-weft, efpecially in the winter time. It is 25 miles 



wide at its entrance, and runs about 9 miles inland, with 

 feveral creeks communicating with it, of which thofe within 

 Barnach ifle, and the point of Claggan, are the moft remark- 

 able. The fouth-weft point of this bay is in N. lat. 54° 6'. 

 W. long. 9^52' M'Kcnzie, &c. 



Blacksod Point, the fouthern point of the Mullet, a 

 peninfula in the weftern part of the county of Mayo, Ire- 

 land, which forms the wellern extremity of Blackfod bay. 

 N. lat. 54° 6'. W. long. 9^ 52'. 



BLACKSTONE, J. in Biography, apothecan,', of whom 

 nothing is known, but that he publiihtd in 1737, " Fafciculus 

 Pia;itarum, circa Harefield, fpontc ntifcentium, cum Appen- 

 dice ad loci naturam fpeftante," 8vo. London. Among many- 

 common, fome very rare plants were difcovered by the aii- 

 thor, and are defcribed in this volur.ie. He alfo publifhed 

 in 1746, " Specimen botanicum, quo plantarum plurium 

 Anglifc indigenarum, loci naturales ilhiftrantur," 8vo» 

 London, an interefting and ufefal work. Haller. Bib. 

 Botan. 



Blackstone, William, S!R, knight and L.L.D. 

 a celebrated Englifh lawyer, was born in London, 

 July loth 1723. and received the firft rudiments of learn- 

 ing at the Charter-houfe, where he was admitted upon 

 the foundnt'onin 1735, and v, hence he was removed, in 1738, 

 to Pembroke college, Oxford. At fchool and in the uni- 

 verfity he was diftinguifhed by his application and proficiency ; 

 and the range of his ftudies, even at an early period, was fo 

 extenfive, that he is faid to have compofed a treatife on the 

 " Elements of Architedturc," for his own ufe at the age of 

 20. This treatife was never publifhed. As he made choice 

 of the proftffio.i of the law, he was entered of the Middle 

 Temp'e, and quitted Oxford in 1744 to purfue ftudies, very 

 different from thofe to which his tafte inclined him at the uni- 

 vertity. This change of his purfuits is feelinglv commemo- 

 rated in the " Lawyer's Farewel to the Mufe," compofed 

 about this time, and publiftied in the fourth volume of 

 Docillev's Mifcellanies. From this period he affiduoudy 

 applied to his profeflional ftudies, rcfiding occafionally in 

 chambers in the Temple, for the convenience of attending 

 the courts, and at otiier times in the univtrfity, to which he 

 was much attached. In 1743 ^^ ^'^^ elefted a fellow of 

 All-Sou!s college, and on the 24th of November 1746 he 

 was called to the bar, and comtnenced the praftice of the. 

 law. Dellitute ot a ready elocution, and of other talents 

 requifite for a popular advocate, his progrefs was flow ; and 

 he had kifure to difehars^e the duties of burfar, or fteward, 

 of All-Souls, which he did with fuch ikill and diligence, as 

 to improve the revenues of the college,, and to aid in com- 

 pleting the magnificent flrufmre of the Codi'ngton library', 

 A treatife which he compofed on this occafiyn is ftfll ufcful 

 in coiiducling the pecuniaiy concerns i;f this fociety. In 

 1749, he was appointed recorder of Whl!:i:r'ord in Bcrk- 

 fliire ; and defirous of more conftani refider.ceat Oxford, he 

 took in the following year the degree of doftor of laws. 

 About this time he publifhed an " Effay on collateral confan- 

 guinity ;" particularly referring to the claim made by the 

 kindred of the founder of All-Souls to a preference in being 

 elefted fellows of thatfociet). It was written, in defence 

 of the college, which had lately rejefted fome of thefe 

 claims ; but the reafoning, though fupported by great 

 learning and ingenuity, is deemed by fome competent 

 judgesinconclufive. lu 1753, Mr. Blackftone, perceiving, 

 after a trial of feven years, that he had no profpeft of fuc- 

 cefs in the courts at Weftminfler, determined to quit London, 

 and to retire to his fcllowfiiip at Oxford. This refolution 

 was eventually veiy favourable both to himfelf and the 

 public. As no public provifion had been made either by 

 the founders of the Engtilh univerfities, or at any fubfequent 



period. 



