12 
the light has passed. If sodium vapour be traversed, then 
the light corresponding to the bright lines of sodium will 
be enfeebled. 
This great law, to which the researches of Stokes and 
Stewart and Angstrém have led, and which has been 
established by the experiments of Foucault, Kirchhoff, 
and Bunsen, may be summed up as follows :—Gases and 
vapours, when relatively cool, absorb those rays which 
they themselves emit when incandescent ; the absorption 
is continuous or selective as the radiation is continuous 
or selective, J. NORMAN LOCKYER 
‘ (To be continued.) 
NOTES 
THE Emperor of Brazil has conferred upon Dr. Warren De 
La Rue the distinction of Knight of the Imperial Order of the 
Rose. 
THE subject of Professor Tait’s Rede Lecture, to be delivered 
on the 23rd inst., will be ‘‘ Thermo-Electricity.” 
A PARAGRAPH has recently appeared in several scientific papers 
quoted from the Zeitschrift ftir Parasitenkunde, stating that 
Prof, Hallier of Jena has described a new potato-disease, which 
made its appearance last autumn in the neighbourhood of that 
town, the disease being indicated by the presence of a purple web 
and the appearance of a number of black spots on the skin, referable 
apparently to the perithecia of a pyrenomycetous fungus. We 
learn from the Rev. M. J. Berkeley that this so-called new 
disease is nothing but the well-known ‘‘ copper-web ” which is in 
some years very destructive to asparagus, mint, and other crops, 
and has been known in some instances to attack the potato. 
The description in the Zeitsch7if¢ is identical with this familiar 
parasite. Figures will be found in Tulasne’s ‘‘ Fungi Hypogzi,” 
under Rhizoctonia, showing that the so-called perithecia are 
spurious, Mr. Broome has detected the form of fructification 
known as conidia, 
LApy LYELL, wife of Sir Charles Lyell, Bart, F.R.S., died 
Jast Thursday, inher 65th year. Her ladyship was the eldest 
daughter of the late Mr. Leonard Horner, F.R.S. 
Durinc the Easter term the following lectures in natural 
sciences will be given at Cambridge :—On Heat (1) Advanced 
(for the Natural Sciences Tripos), by Mr. Trotter, Trinity Col- 
lege, in Lecture-room No. 11, on Mondays, Wednesdays, and 
Fridays at 10, commencing Wednesday, April 30 (2) Elemen- 
tary (for Special Examination and Ist Part of Natural Sciences 
Tripos), on Tuesdays, Thursdays, and Saturdays at II, com- 
mencing Tuesday, April 29. On Chemistry, by Mr. Main, St. 
John’s College, on Tuesdays, Thursdays, and Saturdays at 12, 
in St. John’s College Laboratory, commencing Thursday, April 
24. Instruction in Practical Chemistry will also be given, On 
Palzontology—the Mollusca, &c., by Mr. Bonney, St. John’s 
College, on Tuesdays and Thursdays, at 9, commencing Thurs- 
day, April 24. On Geology—(for the Natural Sciences Tripos, 
Stratigraphical Geology), by Mr, Bonney, St. John’s College, 
on Mondays, Wednesdays, and Fridays, at 10, commencing 
Wednesday, April 23. Elementary Geology (for the First part 
of the Tripos and the special examination), on Tuesdays and 
Thursdays, at 11, commencing Thursday, April 24; there will 
be excursions, of which notice will be given from time to time. 
On Botany (for the Natural Sciences Tripos), by Mr. Hicks, 
Sidney College, on Tuesdays, Thursdays, and Saturdays, at 
11, in Lecture-room No. 1, beginning on Tuesday, April 29 ; 
the lectures during this term will be chiefly on Cryptogamic 
Botany and on Classification. Biology: the Trinity Preelector 
will give a course of Practical Lectures on Elementary Biology, 
on Mondays, Tuesdays, and Wednesdays, at 11 A.M., commenc- 
NATURE 
[May a 7 
7k 
ing Wednesday, April 30. This course is intended as an intro * 4 
duction to the study of both anatomy and physiology. A short 
lecture of about half-an-hour will be given at each meeting, ae ‘ 
lowed by practical work for about 1} or 2 hours. 
THE annual sorée of the Royal Society last Saturday at Bur 
lington House was a great success. “Lhe number of visitors was 
exceedingly large, and the objects exhibited were numerous and 
varied. In the Mathematical Room, Mr. Latimer Clark showed % 
his remarkable experiment of the influence of light on the con- : id 
§ 
ea 
f 
ductivity of selenium, recently described in NATURE, 
a. 
THE office of ‘‘Lord Rector” of a Scotch University is_ cay 
generally regarded as merely honorary, a testimony of the esti- _ 4 
mation in which the students hold the gentleman whom they 
elect. As a rule the Lord Rector acquiesces in this opinion, and 
seldom does more in return for the supposed honour conferred — 
than mark the commencement or close of his three years’ ~* 
tenure of office by making a speech to the students. As might ri 
be surmised, Prof. Huxley, who was recently elected to the 
Lord Rectorship of Aberdeen University, which counts Prof. 
Bain among its staff of teachers, does not regard the office as { 
merely honorary: he intends to take advantage of the position — ie 
conferrred upon him by doing some actual work for the good of — a 
q 
3 
the University. Naturally one of the first grievances he has 
attacked is the medical curriculum, which at Aberdeen, as at ; 
most other medical schools, is hampered by the ‘traditions of | i 
the elders’’ as to the supposed advantages of the dead languages 
to a medical s'udent. Shortly after Prof. Huxley’s election, he — 
received a numerously signed petition from the medical students . 
requesting him to use his influence to obtain the omisssion of 
Greek as a compulsory subject in the preliminary examination. 
Prof. Huxley has given notice that he will bring forward at the — 
next meeting of the University Court a resolution to reform the — 
medical curriculum at Aberdeen, as he considers it at present — 
rather overweighted with classics, and believes that some new 
arrangement’ would probably be exceedingly advantageous, 
especially in the matters of natural history and botany, WN 
WE hear from Mr. Lloyd that living specimens of the Lancelet 
(Amphioxus la nceolatus) have been very recently received at the — 
Crystal Palace Aquarium, from Naples, and are now alive. We e 
hope that Dr. Dohrn will be successful in sending other Jiving- 7 
specimens of this most interesting fish to other Aquaria in ed ’ 
country, so that its affinities and development may be more 
thoroughly worked out and generally understood, 
Mr. THOMAS WILLIAM BRIDGE was on Friday elected toa 
Natural Science Scholarship at Trinity College, Cambridge. 
Mr. Bridge has for some two years worked under Mr. J. W. 
Clark, the Superintendent of the University Museums of Zoology © 
and Comparative Anatomy, and about a month since was ap- 
pointed, by the Professor of Zoology, to the newly-founded post 
of Demonstrator in Comparative Anatomy in the University. 
Dr. Divers, of the Middlesex Hospital, has been appointed — 
to the Professorship of Chemistry in the new Engineering Cole a 
lege at Jeddo. 
Pror, AGassiz has not been behindhand in employing dies 
advantages placed at his disposal by Mr. Anderson’s munificent 
bequest. A programme is already published of a summer course ~ 
of Natural History at Penekese Island, designed chiefly for r 
teachers, and for students preparing to become teachers, Among 
those that Prof. Agassiz is able to include on his staff we find 
the names of Profs. Shaler, Wilder, Packard, and Putnam, and 
every attempt is being made to obtain a sufficient endowment, — 
through the liberality of others, to offer the course free of charge — 
to deserving students, The Superintendent of the United States 
Coast Survey and the United States Commissioner of Fisheries — 
have also promised all the assistance in their power to this excel- 
lent undertaking. 
a 
7) 
