DECEMBER 18, 1913] 
NATURE 
clxv 
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, 110 Illustrations. 
This catalogue has been prepared 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 from 
a practical p.int 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. 
FOSSIL COLLECTION. 
JAMES R. GREGORY & CO. having purchased the well-known 
Collection of Silurian and Coal Measure Fossils. formed by 
the late Henry Johnson, of Dudley, are prepared to sell the 
Collection either separately or as a whole. Apply to 
JAMES R. GREGORY & CoO., 
Mineralogists, &c., 
139 FULHAM ROAD, SOUTH KENSINGTON, S.W. 
Telephone: 2841 Western. Telegrams : ‘‘ Meteorites, London.” 
LIVING SPECIMENS FOR 
THE MICROSCOPE. 
Volvox, Spirogyra, Desmids, Diatoms, Amoeba, Arcella, Actinospherium, 
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, Caryophyllia, 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. 
THE DIRECTOR 
WATKINS & DONCASTER. 
Naturalists and Manufacturers of 
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, &e., Preserved and Mounted by First-class 
Workmen true to Nature. 
All Books and Publications (New and Second-hand) on Insects, 
Birds’ Eggs, &c., supplied. 
86 STRAND, LONDON, W.C. 
(Five Doors from Charing Cross.) 
FULL OATALOGUE POST FREE. 
Sales by Eluction. 
STEVENS’ AUCTION ROOMS. Esvrp. 1760. 
A Sale by Auction is held EVERY FRIDAY 
at 12.30, which affords first-class opportunities for the disposal or 
urchase of SCIENTIFIC AND ELECTRICAL APPARATUS, 
icroscopes and Accessories, Surveying Instruments, Photographic 
Cameras and Lenses, Lathes and Tools, Cinematographs and Filnis, 
and Miscellaneous Property. 
Catalogues and terms for selling will be forwarded on application 10 
Mr. J. C. STEVENS, 
38 KING STREET, COVENT GARDEN, LONDON, wW.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. cr at Colleges, &c. 
66 HATTON G N. Lb N. 
H. HELM, ‘ Rene aR ee eS 
ACTUAL MAKER of ALL K/NDS of X Ray, Geissler and other 
Vacuum Tubes, Mercury arp High Frequency Electrodes, &c. 
List free. 
WEINERATLS. 
Now on view, some choice specimens of 
DATOLITE 
from Parc Bean Cove, Mullion, Cornwall. Probably the last 
lot that will be found in this district. 
A large number of other choice Cornish 
specimens. 
RUSSELL & SHAW, 
38 Gt. James Street, Bedford Row, London, W.C. 
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