810 
ceps of 1482, carried acommentary said to 
be by ‘Campanus of Novara.”* That means 
that everything except the enunciations was 
by Campanus ; for the early notion was that 
all the demonstrations were the work of edi- 
tors. Of course that was entirely errone- 
ous and, as far as the first book is con- 
cerned, a most monstrous error, since that 
book is one of the most deeply studied 
statements that ever was drawn up in any 
branch of thought. 
The Latin text of Euclid which accom- 
panied this commentary had been derived 
indirectly from an excellent Greek text, de- 
cidedly superior to the common traditional 
text of later times; though in certain de- 
tails it was faulty. But thereare many in- 
dications that the translation was not made 
directly from the Greek, but from the Arabic. 
There is said to be a ‘controversy’ as to 
whether the translation was due to Cam- 
panus or not. But as far as I can discover, 
the ‘controversy’ consists in this, that 
everybody who has made any independent 
inquiry into the matter, such as Tiraboschi 
and Charles Jourdain, says that the version 
is that of Adelard of Bath ; while the Ger- 
man writers, none of whom have really 
examined the evidences, either roundly 
assert that it is by Campanus or decline to 
enter into what they call the ‘ controversy.’ 
The commentary of Campanus is very 
unequal. In some places, especially in the 
tenth book, it rises to a high level of mathe- 
matical reasoning; while in some other 
places it is beneath criticism. For the most 
part, it is very respectable. 
Campanus himself has remained an ob- 
scure personage. He has usually gone 
*The colophon of the first edition reads: Opus 
elementorum euclidis megarensis in geometriam ar- 
tem. In id quoque campani perspicassimi commen- 
tationes finiunt. Erhardus ratdolt Augustensis im- 
pressor solertissimus venetijs impressit. Anno salutis 
MCCCCLXXXII Octavis Calendis Junii. Lector 
Vale. Euclid was always confounded with Euclides 
of Megara. 
SCIENCE. 
[N. S. Vou. XIII. No. 334. 
by the name of Campanus, tout court; 
but now and then he has been called Jo- 
hannes Campanus. It appears that Joan- 
nes de Lyneriis, who, about 1310, wrote an 
‘A bbrieviatio Instrumenti Campani,’ so calls 
him ; and thereis other XI Vth-century evi- 
dence to prove that that was his name (see 
Boncompagni, X VII., 783, 784). Inregard 
to his age, a MS. work of Petrus Peregrinus, 
to which internal evidence assigns the date 
1261, refers to the planetary tables of Cam- 
panus (Boncompagni, I., 5), while Roger 
Bacon is said to speak of him asstill living. 
These facts agree with the assertion of 
Baldi (whose life of Campano, dated 1588, 
is given in Boncompagni, XIX., 591), and 
fully proved by Tiraboschi (Storia della. 
Letturatura Italiana, Tomo LV., Libro IT., 
capo ii., $8), that he was chaplain of Pope 
Urban IV., who reigned from 1261 to 1264. 
I think that I can fix the date of the 
commentary upon the ‘ Elements’ within a 
year or so. In the collection of ele- 
mentary mathematical works which have 
been brought together by George A. Plimp- 
ton, Esq., there is a manuscript of this 
commentary upon vellum, written in a very 
handsome, but stiff and slightly elongated, 
book-hand, which might have been written 
at any part of the last half of the XIIIth 
century, though I think it would be sur- 
prising to find that it was as early as 1250. 
Just below the colophon of this MS., where 
the owner of such a book frequently wrote 
his name, one can read in a careful cursive 
hand of, say, the third quarter of the XIIIth 
century, or thereabout, a pious sentence in 
the first person by ‘Jacobus Dei gratia 
Patriarcha Jerusalemitorum.’ Observe 
that one hardly uses the phrase ‘ Dei gratia’ 
except in speaking of oneself. 
It can, therefore, be asserted with con- 
siderable confidence that, soon after this 
MS. was written, it came into the possession 
of a person so describable. But that could 
only be Jacques Pantaleone, who, having 
