———  s 
SEPTEMBER II, 1913] 
NATURE 
XXlil 
MINERALOGY —CRYSTALLOGRAPHY— 
PETROGRAPHY - GEOLOGY, 
Ask for our new 
GENERAL CATALOGUE XVIII. 
(2nd Edition) 
for the use of Middle and High Schools and Universities. 
Part I, 260 pages, r1o Illustrations. 
This catalogue has been prepired with the view of making an exhaustive 
compilation of all educational appliances for the teaching 
of Mineralogy and Geology from a scientific as well as froin 
a practical pvint of view. All the subjects are treated typically, and 
instructive specimens have been selected with the greatest care. A close 
examination of the catalogue will show that owing to its careful compo- 
sition it gives the opportunity of procuring the most complete outfit for the 
various schools for instruction in and the study of the subjects named, 
Catalogue No. 18, Part I, will be sent free on application. 
Part II will appear within the course of the year. 
(Collections and single specimens of Minerals and Fossils. 
Meteorites bought and exchanged.) 
Dr. F. KRANTZ, 
RHENISH MINERAL OFFICE, BONN-ON-RHINE, GERMANY, 
Established 1833. Established 1833. 
METEORITES 
Meteorie Iron and Stones in all sizes and prices. 
Apply stating requirements, &c., to 
JAMES R. GREGORY & CO., 
MINERALOGISTS, &c., 
189 FULHAM ROAD, SOUTH KENSINGTON, S.W. 
Telegrams: ‘‘ Meteorites,” London. 
LIVING SPECIMENS FOR 
THE MICROSCOPE. 
Volvox, Spirogyra, Desmids, Diatoms, Amceba, Arcella, Actinosphzrium, 
Vorticella, Stentor, Hydra, Floscularia, Stephanoceros, Melicerta, and many 
other specimens of Pond Life. Price rs, per Tube, Post Free. Helix 
pomatia, Astacus, Amphioxus, Rana, Anodon, &c., for Dissection purposes. 
THOMAS BOLTON, 
25 BALSALL HEATH ROAD, BIRMINGHAM. 
MARINE BIOLOGICAL ASSOCIATION 
OF THE UNITED KINGDOM. 
THE LABORATORY, PLYMOUTH. 
The following animals can always be supplied, either living 
or preserved by the best methods :— 
Sycon; Clava, Obelia, Sertularia; Actinia, Tealia, Caryopbyllia, Alcy- 
onium; Hormiphora (preserved); Leptoplana; Lineus, Amphiporus, 
Nereis, Aphrodite, Arenicola, Lanice, Terebella; Lepas, Balanus, 
Gammarus, Ligia Mysis, Nebalia, Carcinus; Patella, Buccinum, Eledone, 
Pectens Bugula, Crisia, Pedicellina, Holothuria, Asterias, Echinus, 
Salpa (preserved), Scyllium, Raia, &c., &c. 
‘or prices and more detailed lists apply to 
Biological Laboratory, Plymouth. 
Telephone: 2841 Western. 
THE DIRECTOR. 
WATKINS & DONGASTER, 
CABINETS AND APPARATUS 
FOR COLLECTORS OF INSECTS, BIRDS' EGGS AND SKINS, 
MINERALS, PLANTS, &c. 
N.B.—For Excellence and Superiority of Cabinets and Apparatus 
references are permitted to distinguished patrons, Museums, Colleges, &c. 
A LARGE STOCK OF! INSECTS, BIRDS’ EGGS AND SKINS. 
SPECIALITY.—Objects for Nature Study, 
Drawing Classes, &c. 
Birds, Mammals, &c., Preserved and Mounted by First-class 
Workmen true to Nature. 
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Birds’ Eggs, &c., supplied. 
36 STRAND, LONDON, W.C. 
(Five Doors from Charing Cross.) 
FULL OATALOGUE POST FREE. 
Sales by #Huction. 
STEVENS’ AUCTION ROOMS. Estp. 1760. 
A Sale by Auction is held EVERY FRIDAY 
at 12.30, which affords first-class opportunities for the disposal on 
purchase of SCIENTIFIC AND ELECTRICAL APPARATUS, 
Microscopes and Accessories, Surveying Inst:uments, Photographic 
Cameras and Lenses, Lathes and Tools, Cinematographs and Film:, 
and Miscellaneous Property. 
Catalogues and terms for selling will be forwarded on application ‘o 
Mr. J. C. STEVENS, 
38 KING STREET, COVENT GARDEN, LONDON, W.C. 
GLASS BLOWING 
: ALL KINDS OF SCIENTIFIC AND EXPERIMENTAL GLASS 
BLOWING carried out quickly and correctly from rough sketch 
at Moderate Charges. 
ANY FORM OF GLASS APPARATUS REPAIRED. 
DEMONSTRATIONS given here, or at Colleges, &c. 
aH 66 HATTON GARDEN, LONDON, 
H. HELM, Telephone : 2512 al Boxn! i 
ACTUAL MAEER of ALL KINDS of X Ray, Geissler and other 
Vacuum Tubes, Mercury oe me Frequency Electrodes, &c. 
List free. 
Collections of British and Foreign 
MINERALS, ROCKS, FOSSILS. 
25 Specimens, 5/6; 50 do., 10/6; 100 do., 21/-; 200 do., 42/-. 
20 Coal Measure Rocks and Fossils, 12/6; do., larger, 15/-. 
: In Polished Deal Boxes. 
Inspection. invited of a large stock of Minerals, Rocks, Fossils, and 
Microscopic Objects. Specimens sent on approval. 
Prospectors’ Sets, Blowpipe Cases, Cabinets, Geologists’ 
Hammers, Card Trays, Glass-Capped Boxes, Models of Crystals, 
and all Apparatus for Mineralogists and Geologists. 
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