348 
NATURE 
[ Fan. 27, 
Boston 
Society of Natural History, November 3, 1869.—Mr. 
W. H. Dall made a few remarks upon the distribution of marine 
animals, asserting that their range was influenced more by the 
temperature of the water than by ‘the depth or other conditions. 
He showed that the floating-ice line of Behring Sea (which passes 
between the Pribyloff and St. Matthew groups of islands, touch- 
ing the continent near Kuskoquim Bay) governed the distribution 
of the fish and molluscs of those waters. It is the northern limit 
of all the more southern forms, some of which range as far south 
as Monterey. It is the southern limit of almost all the truly 
arctic species. The fur seal is never found to the north of it, 
though often erroneously spoken of as coming from Behring 
Strait ; the polar bear never passes to the south of this line ; the 
cod invariably keep to the south, and the mullet to the north, of 
it. It is also the limit of distribution of many fuci and seaside 
plants. Where the water is cooled by northern currents, or by 
glaciers, deep-water species of molluscs, especially brachiopods, 
are found at or even above low-water mark, Where the surface- 
water is warm, these molluscs, which in the north are found near 
the shore, are only obtained at a depth of many fathoms. 
Section of Microscopy, November 10.—Mr. R. C. Greenleaf in 
the chair. Dr. H. Hagen called the attention of the section to 
the statements of Professor Listing, of Gottingen, who had 
recently (Nachr. d. kg]. Gesell. der Wissench., 1869, No. 1, and 
Poggendorff's Annalen, 1869, T. xvi. p. 467) given some sugges- 
tions concerning the further improvement of the microscope. In 
all microscopes the dioptric arrangement is now analogous to the 
astronomic spy-glass ; they have but one real image, from which 
the virtual image is formed and brought to the eye of the observer. 
Professor Listing proposes to have two real images, and in this 
way to form three successive augmentations instead of two, as 
before. It is well known that by a prolongation of the draw 
tube, or by increasing the distance between the objective and the | 
eye-piece, the image “becomes successively greater, but the defini- 
tion and penetration is by no means better. 
has made some experiments, and states that with an eye-piece of 
his construction (a double eye-piece with four lenses, similar to 
those of terrestrial telescopes) the magnifying power of the 
instrument, and also to nearly the same degree the penetration, 
is raised, by a tube of 420 millimetres, 20, 28, 55, 97, and 137 per 
cent. (the latter, of course, with diminution of the field), more 
than the same objective (Hartnack,s, No. 7) and eye-piece (No. 3) 
with a tube 200 millimetres in length. The object was /ezro- 
sigma angulatum, and Professor Listing assures us that the 
latent power of the objective is developed by this means in an 
astonishing manner. He also remarked that the so-called Erectors 
have long been used, but always with a low power and a short 
tube. The most advantageous form for the eye-piece would be, 
for the two superior glasses, achromatic lenses from 15 to 20 
millimetres in diameter and with a diaphragm between, having 
an aperture of from § to 9 millimetres. For the two inferior 
lenses, a common Huyghen’s eye-piece would be the best. Such 
a combined eye-piece, with a tube 420 millimetres long, would 
raise the power of the instrument 97 per cent. The use of an 
achromatic condenser adapted for oblique illumination is neces- 
sary for high powers. The experiment was only successfully 
made with the best objectives of English artists, or with the ex- 
cellent new Hartnack objectives. According to his calculation, 
an objective of one millimetre distance will give the first real 
image at a distance of 200 millimetres from the second chief 
point of the objective, and combined with an eye-piece in List- 
ing’s manner, having a power of 25 diameters by itself, and a 
tube 405 millimetres long, the magnifying power of the whole 
instrument would be 5,000 diameters. In the common arrange- 
ment of the microscope, the dioptric cardinal points are in the 
same order as in a concave lens, and the focal distance of the 
whole microscope (not of the objective) would be equal to —5 
millimetres, with a magnifying power of 400 diameters for a 
visual distance of 200 millimetres. In the Listing instrument 
the order of the cardinal points would be inverted and analogous 
to a conyex lens, with a focal distance of the whole microscope 
equal to x ‘04 millimetres, with a magnifying power of 5,000 
diameters. In the first case the objective would have a focal 
distance of 3 millimetres, in the last of 1 millimetre. The dif- 
ference between the two chief points of the whole microscope is 
in both cases nearly equal to the whole length of the tube. In 
the last arrangement the whole microscope is analogous to a 
convex lens with very short focal distance, 
Professor Listing | 
| OBSTETRICAL 
DIARY 
THURSDAY, JANvary 27. 
Roya Institution, at 3—On the Chemistry of Vegetable Products : 
Prof. Odling. 
Roya Society, at 8.30.—Temperature of Strata in Sinking of Rosebridge 
Colliery: E. Hull-—Action of Rays of High Refrangibility upon 
Gaseous Matter: Prof. Tyndall, F_R.S.—Eclipse of Sun as observed in 
United States : J. N. Lockyer, F.R.S.— Theory of Continuous Beams : 
Mr. Heppel.—Remarks on Heppel’s Continuous Beams: Professor 
Rankine. 
Zoo.ocicat Society, 8.30.—On Cooking Pits and Kitchen Middens, 
containing Remains of Dinornis, New Zealand: Professor Owen, F.R.S 
ANTIQUARIES, at 8.30. 
Lonpon INsTITUTION, at 7.30. 
FRIDAY, January 28. 
Royat Institution, at 8.—Graham’s Scientific work ; Prof. Odling. 
Quekerr Microscoricat Crue, at 8. 
SATURDAY, January 20. 
Royau Instirvrion, at 3.—On Meteorology: Mr. Scott. 
MONDAY, January 31. 
Rovat InstiruTE OF RriTisH ARCHITECTS, at 8. 
InstiTUTE OF ACTUARIES, at 7. 
Lonpon INSTITUTION, at 4. 
Mepicat Society, at 8. 
TUESDAY, FEBRUARY 1. 
Roya. Instrtutron, ‘at 3—On the Architecture of the Human Dody: 
Prof. Humphrey. 
Institution oF Civit ENGINEERS, at 8.—Statistics of Income, Fxpendi- 
ture, and Railway management, ‘and their bearing upon future Railway 
policy: J. T. Harrison, C.E. 
PaTHOLoGICcAlL Society, at 8. 
ANTHROPOLOGICAL SocieTy, at 8.—Negro Slaves in Turkey: 
Millengen. 
Syro-EGypTIAN SOcIETY, at 7.30. 
WEDNESDAY, FEevrvary 2. 
Society or Arts, at 8.—On Recent Improvements in Small Arms. 
PHARMACEUTICAL Society, at 8. 
Society, at 8. 
THURSDAY, FEprvary 3. 
Linnean Society, at 8.—Revision of the genera and species of capsular 
gamophyllous ZLzltacee: J. G. Baker, Esq., F.L.S.—On a new form 
of Cephalopodous ova: Dr. Collingwood, F.L.S. 
Major F. 
BOOKS RECEIVED 
F-nGiisH.—Lichenes Britannici: Crombie (Reeve and Co.)—Elementary 
Introduction to Physiological Science (Jarrold and Son).—The American 
Naturalist, No. 11.—The Spherical form of the Earth, a Reply to Parallax ; 
J. Dyer (Triibner and Co).—On the Geographical Distribution and Physical 
Characteristics of the Coal Fields of the North Pacific Coast: Robert 
Brown.—Fresenius’ Analysis, Quantitative, fifth edition Arthur Vacher).— 
Fresenius’ Analysis, Qualitative, seventh edition (Arthur Vacher). 
Foretcn.—Ueber die Gahrung und die Quelle der Muske'kraft: J. Von 
Liebig.—Bulletins de la Société d’ Anthropologie de Paris.—Pfliiger’s Archiv 
fiir Physiologie — Centralblatt fiir die medicinischen Wissenschaften, 
January, 1870. 
CONTENTS Pacr 
Dust AND DISEASE . « 327 
VEGETABLE MoNSTROSITIES. (With Wtustrations:) By ‘ALFRED W. 
I} Taw onlasbio to oligo Soho a oho dG ofe le o 5 9 ces 
ATTFIELD’S CHEMISTRY . . . . = - = «) kode. Sia) isn Oe 328 
Our Book SHELF . . . 
. : . de . . eur 2 
ARE ANY OF THE NEBULA: STAR-SYSTEMS ? (With Illustration.) By a 
RicHakp A. Procror, FR.A.S. . . th 2 eon 
THE Crossness WELL-BORING. (I7th Illustrations.) ic) & ye tr gS: 
UTILISATION OF SEWAGE ... . a ae si Ses 
LETTERS TO THE EpITOR:— 
Kant’s View of Space —Grorcke Henry Lewes; G. Croom 
ROBERTSON; Ws HEISTANDEY, IMONGK §. (01000) nian sie cena 
State Aid to Science . . Cre Orce MHaay fle) 
Use of the word Correlation —W. R. Grove, E.RS fa (Oh (OS Gees GAS 
Rainbow. Golours:— RS. INEWALE . 492 Je ae) sete cena 
Cuckows’ Eggs.—W. J. STERLAND. . : Go oo see 
Dr. Livingstone’s Discoveries.—KEITH Jouxston, jun. 5 We cht 
Physical Meteorology.—Dr. B. Stewart, F.R.S. . . . « + « 337 
Veined Structure in Ice.— Rev. T. G. Bonney... + 337 
Personal Equation of Astronomical Observers.— H. Von DE 'Srapr, 
Ph. D. Bee OF Ol achy/ 
Anatomical Lectures to Female Medical Students. . . . . . 337 
NODES memes se! ce ie tal te) SOT 
On Haze axb Dust. By Proressor Tyxpatt, *RARSS ipo hes eae 339 
SCIENTIFIC SERVARS@: [65 =) = lene ee hone Glan 6 okt 
Borany .. . ee ome Penh cua se em Oo eee! 
Societies AND ACADEMIES: » . s 2 ts ss ee 8 Ser cimey 
Errata.— Page 260, first column, last line: for “ plan” read “position.” 
—Page 269, second column, second line: for ‘‘ supplemented” read *‘ supple- 
mented as soon as possible.”—Page 269, second column, fourth line: for 
“should” read ‘‘ should not ” 
Printed by R. Cray, Sons, & Taytor, at 7 and 8, Bread Street Hill, in 
the City of London, and published by Macmititan & Co,, at the Office, 
63, Bleecker Street, New York.—Tuurspay, January 27, 1870. 
