Fuly 7, 1870 | 
NATURE 
203 
that is 
we 
= 
fo 
f= oO ae 
SS Ee 
Bite = haige (& +e)? 
So that assigning to @any given value, we have a, a’, and thence 
the position of the point on the curve. We may draw the 
2 
2 
he 
hyperbola y?=4 87 + Pe and the ellipse y? = 4 6? — Vid 
and then measuring off in these two curves respectively the 
ordinates which belong to the abscissee, 4 + @ for the hyperbola, 
& — @ for the ellipse, we have the values o + o’ and o - a’, 
which determine the point on the curve. Considering 4, 4, g, 
B as disposable quantities, the conics may be any ellipse and 
hyperbola whatever, having a pair of vertices in common. The 
author then proceeded to draw the curve and point out some of 
its peculiarities. 
Mr. T. Cotterill then gave an abstract of his paper “On the 
intersection of curves, and a collinear correspondence in certain 
réseaus,” going into the discussion of the following theorem :— 
If the assemblage of all the points of intersection of two plane 
curves be said to form an ‘‘ intersect,” and a series of groups of 
points, called the first, second, third, &c., be taken on a plane 
curve of an order > 2, such that the points in every two succes- 
sive groups form an J/yfersect ; then the points in any odd and 
any even group, or in any number of odd and an equal number 
of even groups, also form an Jxtersect. Amongst other applica- 
cations of this theorem, certain exceptions were pointed out in 
the laws laid down concerning the intersection of curves. Thus 
a system of 13 points can be found such that a quartic through 
12 of the points must pass through the 13th, whilst the quartics 
through the 13 points do not intersect again in three fixed points, 
but any such quartic is cut by any other quartic of the system in 
three points collinear with a fixed point on the first quartic. Hence 
arises a correspondence of three collinear points similar to 
Geiser’s correspondence in cubics through seven given points. 
The details of the correspondence, including certain envelopes 
given in the paper, refer to curves of any order, 
Syro-Egyptian Society, June 7.—Mr. W. H. Black inthe 
chair. Mr. Robert Hay, of Limplum, exhibiteda large and un- 
usually fine collection of Egyptian Antiquities, the property of 
his late father, author of ‘‘ Views in Cairo,” by whom they were 
collected between the years 1828-33. They consist chiefly of 
five classes of objects. Bronzes, terra cottas, vases, funereal re- 
mains, and amulets in precious stones, and porcelain, besides 
six large mummies with their outer cases more or less complete. 
Mr. Bonomi, who gave an explanatory lecture on the various 
antiquities, pointed out the following objects as being noteworthy 
either from their rarity or beauty. 
1. A large and fine bronze figure of Khonso, twenty-six inches 
high (No. 32), partly overlaid with antimony, and enamelled 
with a white opaque pigment, to represent the mysterious gar- 
ment of that divinity. The head, hands, and collar had been 
gilt, and the eyes, staff, and mens inserted, but these latter had 
been lost before it was obtained by its late owner. The work- 
manship of the statue is of the best Theban art, and is an admir- 
able illustration of the great chemical knowledge possessed by 
the ancient Egyptians. 
2. A small terra cotta statue of a Royal Scribe (706), habited 
in the costume of the nineteenth dynasty. The seed bag hangs 
over the right shoulder instead of the left as usual, and the 
crossed hands clasp on his breast a figure of a hawk with human 
head and expanded wings. This bird symbolised the soul in 
Egyptian theroglyphy, and a like figure is used in Psalm xi. 1, 
Unfortunately this statue has been much injured. A second and 
more perfect example in limestone (No. 159) was also exhibited. 
Both rare specimens. 
3. Four statues, one in bronze, one in stone, and two in 
porcelain (Nos. 12, 116, 846), of the Great Theban Divinity, 
Amun Ra. These figures are of rare occurrence in any material, 
as about the reign of Amenophis III., the worship of Amun Ra 
was overthrown, and his name sedulously erased from all in- 
scriptions throughout Egypt, even upon the top of the loftiest 
obelisks. In a later period, that of Ramesis II., however, the 
worship of this divinity was resumed, and his name again appears 
on the monuments. 
4. A porcelain amulet. (894), representing a human-headed 
scorpion, having the tail turned up over the back. The head of 
this figure was originally surmounted by a crown or head-dress. 
Exquisite finish, probably unique. 
5. A wooden tablet (539) of the kind described by some 
writers as astronomical, but more probably a votive stete dedi- 
cated to Homs, and intended as a charm or mystical talisman 
against accidents, the evil eye, and malign influences generally. 
6. Several staves (572) in hard wood having a projecting spur 
or branch at the top. These staves were carried by the priests 
in funeral processions, and for some unknown reason it was 
necessary that they should be furnished with a short projection 
at a certain angle near the upper extremity, for if this were 
wanting in this natural stick it was supplied by art; such a 
specimen so furnished (573) was also exhibited. 
7. A small bronze figure of the Goddess Pasht holding a 
shield in her right hand, with the left extended.—The preced- 
ing formed only a part of the objects successively noticed by 
the lecturer. Many domestic articles, models, lucernze and _per- 
sonal trinkets remained, which from the lateness of the hour 
could not further be commented upon. The explanations of Mr. 
Bonomi were afterwards supplemented by various remarks from 
Messrs. Cooper, Cull, Hewlett Ross, Williams, Mills, Christie, 
Drach, W. H. Black, and other gentlemen, and it was further 
announced by the chairman (Mr. W. H. Black) that a special 
meeting would be convened for the first Tuesday in July, when 
the drawings, MSS., and papyri of the late Mr. Hay would be 
exhibited, and also a collection of photographs lately sent from 
Syria by Dr. Cull, in illustration of the same, It may be grati- 
fying to our antiquarian friends to know that by special permis- 
sion of the Council of the S.-E.S., the collection may be viewed 
during this present month at their rooms, No. 22, Hart Street, 
W.C., between the hours of eleven and four, where all particulars 
respecting the destination of the antiquities may be obtained. 
DUBLIN 
Royal Irish Academy, June 13.—Rev. Professor Jellett, 
F.T.C.D., president, in the chair. The minutes of the 
previous meeting were read and confirmed. Dr. Sigerson, F.L.S., 
read a paper entitled ‘‘ Further Researches on the Atmosphere.” 
He showed that his former discoveries had been confirmed by 
later investigations, and proceeded to detail the results of his 
examination of ‘special atmospheres.” His lecture was illus- 
trated with large diagrams representing some of the objects dis- 
covered. In ‘‘iron factory ” air he found carbon, ash, and iron. 
The iron was discovered to be hollow balls averaging one two- 
thousandth part of an inch in diameter, their shell being only 
one thirty-thousandth, and the iron was then found to be trans- 
lucid. In ‘‘shirt factory” air there were found to be filaments 
of linen and cotton with minute eggs. The air of thrashing and 
oat-mills had fibres, fragments, starch grains, and spores. Scutch 
mills, from the character and quantity of the spongy, spiky dust 
and its effects, he declared to be human slaughter-houses. By a 
suggested alteration, the works could be kept free of the dust, 
and many lives saved. In the air of printing offices antimony 
was expected, and Dr Sullivan’s analysis confirmed the expecta- 
tion. It is, probably, present to an injurious extent in type- 
foundries. Stable air was shown to contain scales and hairs, and 
hair-dressers hada similaratmosphere. Smoke being microscopi- 
cally examined, the tobacco-smoker’s air was shown to contain 
globules of nicotine. He concluded by stating conclusions 
arrived at with regard to lung-functions and contagion. The 
results of Dr. Sigerson’s investigations proved, as might be ex- 
pected, that the air in special workshops contained floating in it 
particles of the débris of the different materials operated on in 
these particular localities. Some discussion followed, at the 
conclusion of which, on the motion of Prof. Sullivan, the paper 
was referred to the Council for publication. John P. Keane, 
C.E., Calcutta, and Hugh Leonard, Kylemore, were elected 
members of the Academy. 
PARIS 
Academy of Sciences, June 20.—M. R. Clausius presented 
a note on a quantity analogous to the potential and on a theorem 
relating to it. M. Bertrand communicated a note by M. G. 
Darroux on the surface of the centres of curvature of an algebraic 
surface.—A memoir was read by M. Maurice Levy on the general 
equations of the internal movements of ductile solid bodies beyond 
the limits at which elasticity can restore them to their original 
state.—The following papers on subjects connected with physics 
were presented to the meeting:—On the variations of tempera- 
ture produced by the mixture of twoliquids, by M. Jamin, upon 
