cum alterius manu ducatur, ipse parum videns; aut denique cum vestigia lumine adhibito regat: similiter cum quis experimenta omnigena absque ulla serie aut methodo tentet, ea demum mera est palpatio; cum vero nonnulla utatur in experimentando directione et ordine, perinde est ac si manu ducatur: atque hoc illud est quod per Experientiam Literatam intelligimus. Nam Lumen ipsum, quod tertium fuit, ab Interpretatione Naturæ, sive Novo Organo, petendum est.

Literata Experientia, sive Venatio Panis, modos experimentandi tractat. Eam (cum desiderari posuerimus, neque res sit plane perspicua) pro more et instituto nostro aliquatenus adumbrabimus. Modus Experimentandi præcipue procedit, aut per Variationem Experimenti; aut per Productionem Experimenti; aut per Translationem Experimenti; aut per Inversionem Experimenti; aut per Compulsionem Experimenti; aut per Applicationem Experimenti; aut per Copulationem Experimenti; aut denique per Sortes Experimenti. Universa vero ista cohibita sunt citra terminos Axiomatis alicujus inveniendi. Illa enim altera pars de Novo Organo omnem Transitionem Experimentorum in Axiomata, aut Axiomatum in Experimenta, sibi vindicat.

Variatio Experimenti fit primo in Materia; scilicet quando Experimentum in jam cognitis, certæ materiæ fere adhæsit; nunc vero in illis quæ similis sunt speciei tentetur; veluti Confectio Papyri in pannis linteis tantum probata est, in sericis minime, (nisi forte apud Chinenses); neque rursus in filaceis, compositis ex setis et pilis, ex quibus conficitur (quod vocamus) Camelotum ; neque denique in laneis, gossipio,' et pellibus; quan

1 Cotton paper was known long before that made from rags. It seems probable that the art of making paper came to the west of Europe from

quam hæc tria postrema magis esse videntur heterogenea; itaque admisceri possint potius quam per se utilia esse. Item insitio in arboribus fructiferis in usu est; in arboribus silvestribus raro tentata; licet perhibetur ulmum in ulmum insitam miras producere foliorum umbras. Insitio etiam in floribus rara admodum est; licet hoc jam cœperit fieri in rosis muscatellis, quæ rosis communibus fœliciter inoculantur. Etiam variationem in parte rei inter variationes in materia ponimus. Videmus enim surculum in trunco arboribus insitum fœlicius pullulare, quam si terræ indatur. Cur non et semen cepæ capiti alterius cepæ viridis inditum fœli-. cius germinet, quam si nudæ terræ commissum fuerit? Atque hic radix pro trunco variatur ; ut hæc res insitio quædam in radice videri possit. Variatio Experimenti fit secundo in Efficiente. Radii Solis per specula comburentia calore ita intenduntur, ut materiam quæ ignem facile concipiat accendere possint: num et radii Lunæ per eadem ad lenissimum aliquem gradum teporis actuari possunt; ut videamus, utrum corpora omnia cœlestia sint potestate1 calida? Item calores radiosi, per specula scilicet, intenduntur: num etiam calores opaci (quales sunt lapidum et metallorum antequam candeant) idem patiuntur, an potius sunt luminis in hac re

Constantinople, and that our word quire, of which the equivalent in Low Latin is manus, is a token of its Greek origin, and means properly a handful of paper.

1 The elements and their primary qualities (hot, cold, moist, dry), being confined to the sublunary part of the universe, nothing which lies beyond the region of fire, which is next to the orb of the moon, can, according to the school philosophy, be actually or formally hot. But the heavenly bodies, as the sun manifestly is, may be hot potestate · that is, may have the power of heating whatever is susceptible of their operation. known that the moon's rays have never as yet been sufficiently concentrated to produce any perceptible degree of heat.

It is

partes nonnullæ ?! Item succinum et gagates fricata paleas trahunt: num etiam et ad ignem tepefacta ? Variatio Experimenti fit tertio in Quanto; circa quod diligens admodum est adhibenda cura, cum hoc multi circumstent errores. Credunt enim homines, aucta aut multiplicata quantitate, pro rata augeri aut multiplicari virtutem. Et hoc fere postulant et supponunt, tanquam res sit mathematicæ cujusdam certitudinis; quod omnino falsissimum est. Globus plumbeus unius libræ a turri demissus (puta) decem pulsuum spatio ad terram descendit num globus duarum librarum, (in quo impetus iste motus, quem vocant, naturalis duplicari debet,) spatio quinque pulsuum terram feriet?

At

ille æquali fere tempore descendet, neque accelerabitur juxta rationem Quanti.2 Item sulphuris (puta) drachma una, semilibræ chalybis admixta, eam fluere faciet et colliquari: num igitur uncia sulphuris quatuor libris chalybis ad colliquationem sufficiet? At illud

1 The researches which Bacon here suggests, in which obscure radiant heat is dealt with in the same manner as luminous heat, have been recently carried on with great success, and have led to many interesting results. The question as to the nature of the essential or formal connexion between heat and light remains however as yet unanswered, though it may be hoped that it will shortly be satisfactorily solved.

Telesius, of whom more than of any one else Bacon was a follower, maintained that heat and light were "contubernales naturæ," and that where one was present the other must be present too. Bacon, with a more subtle insight into nature, proposed to trace the analogy which might exist between them in cases where, sensibly at least, the dogma of Telesius seemed unfounded.

2 Long before the publication of the De Augmentis, the theory of the acceleration of falling bodies, which of course includes the fact that all bodies fall from rest with equal velocities (the resistance of the air being set aside), had been made known by Galileo. The experiments which he made about the year 1590 to show the absurdity of the received opinion that the velocity of falling increases as the mass of the falling body led to his leaving Pisa, where he had made them, and where he had in consequence been involved in disputes with the adherents of the Peripatetic philosophy.

non sequitur. Certum enim est, obstinationem materia in patiente per Quantitatem augeri amplius, quam activitatem virtutis in agente. Porro Nimium æque fallit ac Parum. Etenim in excoctionibus et depurationibus metallorum error est familiaris; ut ad excoctionem promovendam, aut calorem fornacis aut additamenti quod injiciunt molem augeant. At illa supra modum aucta operationem impediunt; propterea quod vi et acrimonia sua multum ex metallo puro in fumos vertant et asportent; ut et jactura fiat, et massa quæ remanet magis sit obstinata et dura. Debent igitur homines ludibrium illud mulieris Æsopi cogitare; quæ sperarat ex duplicata mensura hordei gallinam suam duo ova quotidie parituram. At illa impinguata nullum peperit. Prorsus non tutum fuerit alicui Experimento Naturali confidere, nisi facta fuerit probatio et in minore et in majore Quanto. Atque de Variatione Experimenti hactenus.

Productio Experimenti duplex; Repetitio, et Extensio; nimirum, cum aut experimentum iteratur, aut ad subtilius quiddam urgetur. Repetitionis exemplum tale sit. Spiritus Vini fit ex vino per distillationem unicam; estque vino ipso multo acrior et fortior: num etiam spiritus vini ipse destillatus, sive sublimatus, seipsum fortitudine æque superabit ? At Repetitio quoque non absque fallacia est. Etenim tum secunda exaltatio prioris excessum non æquat, tum etiam sæpenumero per Iterationem Experimenti, post statum sive acmen quandam operationis, tantum abest ut progrediatur natura, ut potius relabatur. Judicium igitur in hac re adhibendum. Item Argentum Vivum, in linteo aut alias in medio plumbi liquefacti, cum refrigescere cœperit, insertum, stupefit, nec amplius fluit: num et

idem argentum vivum, si sæpius immissum fuerit, ita figetur ut fiat malleabile? Extensionis exemplum tale sit: Aqua in summo posita, et pensilis facta, et per rostrum vitri oblongum in vinum dilutum immersa, separabit aquam a vino; vino in summum se paulatim recipiente, aqua in imo subsidente: 1 num etiam, quemadmodum vinum et aqua (corpora scilicet diversa) hoc ingenio separantur, possint quoque partes vini (corporis nimirum integri) subtiliores a crassioribus separari; ut fiat tanquam destillatio per pondus, et in summo reperiatur aliquid spiritui vini proximum, sed forte delicatius? Item Magnes ferrum integrum trahit: num etiam frustum magnetis, in dissolutione ferri immersum, ferrum ad se alliciet et se ferro obducet? Item, Versorium Acus Nautica se ad polos mundi applicat: num etiam eadem via et consecutione qua cœlestia? Videlicet, ut si quis acum in contrario situ, hoc est in puncto Australi, ponat, et paulisper teneat, ac deinde vim omittat; num forte acus ad Septentriones se conferet, eligendo potius rotare per occidentem in situm desideratum quam per orientem? Item, Aurum argentum vivum, juxta positum, imbibit: num vero aurum recipit illud argentum vivum intra se, sine extensione molis suæ, ut fiat massa

1 This experiment is more minutely described in the Sylva Sylvarum, i. 14. The water in the inverted glass or phial is maintained by the pressure of the atmosphere at a higher level than that of the wine and water into which the neck of the vessel containing it is inserted, but as the density of the water is greater than that of the diluted wine, it is in a position of unstable equilibrium. But for friction &c. the equilibrium could not practically exist at all; and after a little while it ceases to do so, the water gradually subsiding to the bottom and forcing the wine and water or some part of it into the vessel, which originally contained only water. The water for a considerable time passes without mixing through the wine and water; but of course there is no separation between the wine and the portion of water with which it was originally mixed, and the experiment succeeds just as well with pure as with diluted wine.