Page:Cyclopaedia, Chambers - Volume 1.djvu/264

 BOL

( 114)

BOM

Attraction of the Particles of Water around 'em ; or by break- ing anrl feparating the little Spherules of Water, and fo in- creasing the Ratio of their Surface to their folid Content. There will therefore be a constant Flux of Water from the Bottom of the Veffel to the Top ; and confequently a re- ciprocal Flux from the Top to the Bottom : ('. e. The up- per and under Water will change Places ; and hence we have the Rcafon of that Phenomenon, of the Water's be- ing hot at Top fooner than at Bottom. Again, an intenfe Heat will diminifh the fpecifick Gravity of Water, fo as not only to make it mount in Water, but alfo in Air ; whence arifc the Phenomena of Vapour and Smoak : Tho the Air inclofed in the Interfaces of the Water, muft be al- lnw'd a good fhare in this Appearance : for that, Air being dilated, and its Spring iirengthned by the Action of the Fire, breaks its Prifon, and afcends thro the Water into the Air ; carrying with it fome of the contiguous Spherules of Water, fo many as fliall hang in its Villi, or as can adhere immediately to it. The Particles of Air in the feveral In- terlaces of the fluid Mafs thus expanded, and moving up- wards, will meet and coaiefce in their Paffage ; by which means great Quantities of the Water will be heav'd up, and let fall again alternately ; as the Air rifes up, and again paffes from the Water : For the Air, after Coalition, tho it may buoy up a great heap of Water, by its Elasticity while in the Water, yet can't carry it up together with itfelf into the Atmotphere ; fince when once got free from the upper Surface of the Water in the Veffel, it will unbend itfelf in the Atmofphere, and fo its Spring and Force become juft equal to that of the common unheated Air. Add to this, that were the Spring and Motion of the Air fufficient to carry up the Water with it, yet it would not have that Effect ; but the Water wou'd run off at the Extremities of the Air ; all, except fo much as mould be either entangled in its Villi, or immediately adhere to its Surface by Attrac- tion : And hence we lee the Reafon of the principal Phas- nomenon of Soiling, vis. The fluctuating of the Surface of the Water. See Ebullition, and Effervescence.

Water, only lukewarm, boils very vehemently in the Re- cipient of an Air-Pump, when the Air is exhaufted : The Reafon is obvious ; for the Preffure of the Atmofphere be- ing taken off from its Surface, the Air included in the In- terstices of the Water, dilated by a feeble Heat, has Spring

enough to heave up the Water, and difengage itfelf.

When the Water ceafes boiling, it is again excited thereto by pouring cold Water upon the Recipient ; and when it boih the moft vehemently, ceafes by pouring on hot Water : The Reafon whereof is fcarce guefs'd at. SceHEAT,FiRE,c^c.

BOLE, in Medicine, is us'd, in the general, for feveral Kinds of Earths that enter Galenical Preparations, and are ufed by Painters and other Artifts. See Earths.

Bole-ARMONIAC, or Ammoniac, is a kind of Earth, of considerable Medicinal Virtue, brought from Armenia. yi'he Phyficians fometimes call it Rubrica Synopica, from the City of Synope, where it is fuppos'd to be found. 'Tis of a pale red Colour, and partakes much of the Nature of Sione ; but foft, fat, friable, eaiily pulveriz'd, and flicks to the Tongue. 'Tis efleem'd Deflccative and Stiptic; in which Quality 'tis us'd in feveral Difcafes, both internal and external. This $0/1; is eafily falfify'd ; and the Merchants frequently fell Lcmnian-Farth in lieu thereof. Mattbiolus fays, 'tis found in Gold, Silver, and Copper Mines. See Ammoniac.

Bole of the Levant, is a Medicinal Earth brought from the Levant ; nearly of the fame Nature, and having the fame Ufes with the Bole-Armoniac. 'Pomet fays, there is no fuch thing among us, as either true Bole-Armoniac, or 'Bole of the Levant ; and that all the Soles now in ufe, are brought either from the Provinces of France, or the neighbouring Countries. But this does not feem fufficient- ly warranted ; and the New T'arifs, or Duties on Goods imported into France, which mention 'em both, make it credible that there arc of either kind imported into that Kingdom. Indeed, it appears, that 'tis the Levant Sole which paffes among us for the Armoniac : It enters feveral Com positions, particularly 'Biafcodmm, to give it the Co- lour, t$c.

BOLLANDISTS, a modern Term, now become of fome Confequence in the Republick of Letters. The Bol- landijls, are certain Jcfuits of Ant-werp, who have been a considerable Time, and continue fbill employ 'd in collec- ting the Lives of the Saints. As we find frequent Occa- sion to quote that learned Body in this Work, and are in- debted to 'em for feveral excellent Obiervations that occur therein ; the Reader will not be difplcas'd to find the Oc- cafion of their Name.

In the beginning of the XVIIth Century, F. Hcribert Rofiveide, a Jefuit of Autiverp, laid a Design of collecting the Lives of the Saints, as wrote by the Original Authors, with Notes, like thofc added to his Lives of the Fathers, to clear obfeure Paffages, and dittinguilh the Genuine from the Spurious : He died in itfao, e'er the Work was begun. The Year following, y. Bollandus, a Jefuit of the fame

Houfe, took up the Design ; and whereas Rofu-eide only propofed to collect the Lives already compofed, Bollandui undertook, where there was no Life of a Saint extant, to compofe new ones from the Authors who had mention'd 'em. In 1S35, he took in G. Hcnfchenius a Partner with him; and in 164.1, publifh'd the Saints of the Month of January, in two large Volumes, Folio. In 1650, F.'Pape- broch became an Affociate ; and, Henfchenins dying, F. Baert, Janning, Sollier, and Raye were call'd in, who are ftill alive, and continue the Work : whereof, in 80 Years, there have appear'd 14 Volumes, for the firft fix Months of the Roman Calendar.

BOLT-HEAD, the fame as Matras ; a Veffel ufed by the Chymifts, fee Matras.

BOLTING, a Method of Pleading, or Arguing, in ufe in the Inns of Court ; inferior to Mooting. The Cafe is ar- gued first by three Students, then by two Sarrifcers ; a Se- nior fitting Judge. The Word came from the Saxon Bolt, an Houfe, becaufe done privately within Doors for Inftruc- tion. See Bencher, and Mooting.

BOLTS of Iron, in Building, are diftinguifli'd into three Kinds, 'Plate, Round, and' Spring-Bolts.

Bolts, or Iron Pins in a Ship are of feveral forts : As, Ring- Bolts, ferving for the bringing to of the Planks, $$c. 'Drive- Bolts, ufed to drive out others ; Set-Bolts, employ'd for forcing the Planks and other Works, and bringing them clofe to one another ; Rag-Bolts, on each fide full of Jags or Barbs, to keep them from flying out of their Holes ; Clench-Bolts, for the fame end clench'd, or faften'd at the Ends where they come thro ; Fore-Bolts, made like Locks with an Eye at each end, whereinto a Forelock of Iron is driven to prevent starting out ; Fender-Bolts, made with long and thick Heads, ftruck into the uttermost Bends or Wales of a Ship, to faveher Sides from Bruifes and Hurts.

BOLUS or Bole, in Medicine, an extemporaneous Form of a Medicine, of a foft Consistence, fomewhat ex- ceeding that of an Electuary, and of the Quantity of one Dofe ; contrived principally for the fake of fuch as have an Aversion to potable Medicines; as alfo for the better Conveyance of certain Preparations of Mercury, Antimo- ny, &c. which by their Weight would fink to the bottom of the Glafs, were they mix'd with Fluids. There are Bolus's of various kinds, made with Electuaries, Confec- tions, Conferves, Pulps, Pouders, Salts, Oils, Effences, Extracts, Syrups, igc. fome of which Ingredients muft always have Solidity or Drinefs enough, to give a Confif- tence to thofe that are Liquid.

BOMB, a large Granada, or hollow Iron Ball, or Shell fill'd withGunpoudcr, and furnifh'd with aFllfee, or wooden Tube full of a Combufcible Matter; to be thrown out from a Mortar. See Mortar.

The Method of preparing a Bomb is as follows : A hollow Iron Globe A B, (Tab. 'Pyrotechnia, Fig. 1.) is cafi pretty thick, having a round Aperture A, by which it may be fill'd and lighted; and circular Handles CD, for the commodious putting it into the Mortar. To prove whether it be ftaunch, after heating it red-hot on the Coals, it is expos'd to the Air, fo as it may cool gently : for fince Fire dilates Iron, if there be any hidden Chinks or Perforations, they will thus be open'd and enlarg'd; and the rather, becaufe of the Spring of the included Air continually acting from within. This done, the Cavity of the Globe is fill'd with hot Water, and the Aper- ture well ftopp'd ; and the outer Surface wafh'd with cold Water and Soap : So that if there be rhe fmalleft Leak, the Air, rarefy'd by the Heat, will now perfpire, and form Bub- bles on the Surface. If no Defect be thus found in the Globe, its Cavity is fill'd with whole Gunpouder ; a little Space, or Liberty is left, that when a wooden Tube A E, of

Figure of a truncated Cone, is driven thro the Aperture faften'd with a Cement made of Quick Lime, Afhes.

the Fig; and faft

Brickduft, and Steel-filings work'd together in a glutinous Water ; or, of four Parts of Pitch, two of Colophony, one of Turpentine, and one of Wax ; the Pouder mayn't be bruis'd. This rube is fill'd with a Combuftible Matter, made of two Ounces of Nitre, one of Sulphur, and three of Gun- pouder-duft, well ramm'd. This Fufee fet on fire, burns flowly till it reach the Gunpouder, which goes off at once, burfhng the Shell to pieces with incredible Violence : Whence the ufe of Bombs in befieging Towns. Special Care, however, muft be taken, that the Fufee be fo proportion'd, as that the Gunpouder don't take Fire e'er the Shell arrives at the deffin d Place ; to prevent which, the Fufee is frequent- ly wound round with a wet clammy Thread.

Bombs being made of different Magnitudes, it may be proper to exhibit fome of their Dimenfions ; as in the follow- ing Table.

Diam. of Bomb. 17, In. 10 11, 8

8

Thic of I
 * In.

I

0,10

knefs

3omb

2, 10

,18

Diam.of Aperr.

,20

,i<$

,10

Quant, of Gunpoud #

48 1b.

15 4

Weight ofBomb.

490 lb. 130 40

Others