five others ought to be added to the list, of whom one, Benedict XIII.,' was the first by whom the ominous by-word, "Non videbis annos Petri," was shown to be not necessarily true. Why the popes live so short a time after their elevation was an old question. Alexander II. proposed it to Peter Damiani, who answered it by saying that providence meant to show us how transitory a thing is human greatness.

Peter Ravennas, some centuries later, sought to explain the fact by natural causes. He gives a list of all the popes, enumerating the number of years during which each reigned, a thing in all cases, or in almost all, well ascertained, whereas the age at which a pope has died cannot always be discovered.

The Historia Vita et Mortis is the only work of its author in which I have been able to find distinct evidence of his acquaintance with any of the writings of Roger Bacon. It has often been said that the four idola of Francis Bacon are derived from the four hindrances to knowledge mentioned in the Opus Majus, and no doubt it is possible that this is true. But except the sameness of the number, there is not much analogy between them; and the number four presents itself to the mind in so many combinations that it is not remarkable that it should enter into two independent classifications.2

As for what is said that Roger Bacon had, like his namesake, asserted the necessity of observation and experiment, we need not look so far back to find writers of whom we may suppose that in this respect Francis

Pedro de Luna, who ought in strictness to be accounted an antipope. 2 Moreover, the number of F. Bacon's Idols was originally three. See Vol. I. pp. 159 and 190.-J. S.

Bacon was the disciple. Nor is it likely that Bacon studied an author, almost all whose works were still in manuscript, and who apparently belonged to a class of writers whom he held in very little respect. But of Roger Bacon's tract De Mirabil. Potest. Artis et Naturæ, an English translation was published in 1618, from a copy in the possession of the occult philosopher Dr. Dee. In this we find one or two stories which are repeated in the Historia Vita et Mortis, but which Bacon however disbelieves, and not without reason. That of the Lady of Formerey is clearly a legendary tale; how she was seeking a white doe, and how she met with a forest ranger, who had renewed his youth by anointing himself with an ointment which he had found somewhere within the verge of the forest.1 Roger Bacon's treatise De Retard. Senect. Accidentibus was published in English in 1683. I do not find any reason for supposing that Bacon was acquainted with it. It contains one mystical chapter touching an occult method for the recovery of youth which the translator supposes, and perhaps rightly, to relate to a practice in support of which a passage of the Old Testament has been often quoted. A celebrated book was written in the middle of the last century on the same subject, or on something akin to it.2 But it has unfortunately not been found possible by any embrace to

1 She is called the Lady of the Wood in Dee's version, and in the original text published in the Bibliotheca Chemica Curiosa, Domina de Nemore. But in the edition published in Paris in 1542, and in an extract in the Theatrum Chemicum, her title is Domina de Formerey, from which the other reading may easily have been corrupted.

2 "Hermippus Redivivus," by Cohausen. The title is taken from an apocryphal inscription commemorating the death of one Hermippus at the age of 115, and recording the means whereby he was enabled to live so long.

hinder the flight of youth, or to recall it when it has fled.

Ter frostra comprensa manus efficit imago,

Par levitas ventis nigroque simillima stano.

Bacon alludes briefly to the same idle fancy, and refers in doing so to Marsilius Ficinus, from whose treatise De Vitá producendú he has taken one or two remarks. With the Theognosta of Cardan he was apparently not acquainted. The second book of it treats of the prolongation of life, and Bacon would probably have quoted from it the reply of a kinsman of Cardan's who affirmed that his long life was owing to his never being out of doors before sunrise or after sunset. The rule is at least as good as that of the old man whom Bacon quotes, who always ate before he was hungry, and drank before he was thirsty. Another of these oracular sayings," Oil without, honey within," which Bacon ascribes to the mythical Johannes de Temporibus, seems to be more justly due to Democritus, to whom it is attributed in the Geoponica. That of Pollio Romilius is much to the same purpose-"Intus mulso, foris oleo."

Pliny and Aristotle are Bacon's principal authorities for what is said of the ages of different kinds of animals. From this part of the subject Bacon draws some inferences which are not perhaps without value.

The whole treatise concludes with thirty-two " Canones Mobiles," or provisionally affirmed results. They contain the sum of his theory, of which the passage I have quoted from Haller seems to give an adequate idea.

FRANCISCI

BARONIS DE VERVLAMIO,

VICE-COMITIS SANCTI ALBANI,

HISTORIA VITÆ ET MORTIS.

SIVE

TITVLVS SECVNDVS

IN HISTORIA NATURALI ET EXPERIMENTALI

AD CONDENDAM PHILOSOPHIAM:

QUE EST INSTAURATIONIS MAGNE PARS TERTIA.

LONDONI,

IN OFFICINA IO. HAVILAND, IMPENSIS MATTHÆI LOWNES.

1623.