cxcvi NATURE 
Se 
COMPTES RENDUS 
OBSERVATION & REASONING 
PAPERS, POPULAR AND SCIENTIFIC, 
BY 
J. Y. BUCHANAN, M.A., F.R.S., 
Commandeur de P'Ordre de Saint Charles de Monaco. 
With 14 plates. Demy 8vo. Price 7s 6d net. 
As the title indicates, the hook consists of ‘accounts 
rendered’ of work done at different times, in different 
places, and on different subjects. Of the scientific com- 
munications, the most important are those concerning the 
Natural History of Ice and Steam. The contributions 
to newspapers concerning matters of public interest at 
the time have been reprinted because they are of public 
interest still. 
BY THE SAME AUTHOR 
SCIENTIFIC PAPERS 
VOL. I 
(Oceanographical) 
With portrait, maps, charts, and diagrams. Demy 8vo. 
Price 5s net. 
Cambridge University Press 
London: Fetter Lane. C. F. Clay, Manager 
Edinburgh : roo Princes Street 
Photomicrography 
The difficulty of securing correct contrast, 
the chief problem in photomicrographic 
work, can be largely overcome by the use of 
Wratten M Plates and Screens. Wratten 
M Plates are sensitive to all colours, 
the emulsion is of extremely fine grain, 
and the plates possess high resolving power. 
Wrile for a copy of ‘ Photomicro- 
graphy,”' second edition, price 3d. post free 
Kodak Ltd. (Wratten Division), 
Kingsway, London, W.C. 
[FEBRUARY 22, 1917 
THE “FORTINETTE” 
STANDARD. BAROMETER 
(Each barometer is marked ‘‘Fortinette.”) 
Registered Design No. 420,297. t 
Designed to meet the requirements of Students and : 
others who find the need of a Barometer which will give — 
exact readings, and cost but a moderate sum. 
g Used for demonstration purposes in all the 
principal Science and Technical Cole ae ‘ 
adopted by the L.C.C. for use in their Classes. 
N.B. We wish to emphasize that 
this is a STANDARD BAROMETER, 
made on the SAME principle as 
the larger Fortin’s Barometer, 
and gives readings to -01 inch 
and ‘1 millimetre. : 
We confidently recommend this Instrument for use as 
. a “Standard” in Colleges and Schools, private Observa- 
tories, and by Gas and other Engineers. 
Price complete, mounted as illustrated, 
£25 5 oO 
Nat. Phys. Lab. Certificate, if desired, 10s. extra. 
GLAZED CASE (Oak) with lock, to contain above 
Barometer, B22 2 O 
NATURE says :—** Provides an accurate 
instrument at a moderate cost.” 
DESCRIPTIVE CIRCULAR POST FREE. 
Sole Manufacturers and Proprietors of the Regd. Design: 
PASTORELLI & RAPKIN, Ltd. (ESTA®), 
46 HATTON GARDEN, LONDON, E.C. 
AOTUAL MAKERS OF ALL KINDS OF METEOROLOGICAL INSTRUMENTS. 
Contractors to H.M. Government. 
pe- ILLUSTRATED PRICE LISTS POST FREE 
*,* We pay carriage and guarantee safe delivery within 
U.K. on all our instruments. 
Scientific Instruments 
OF ALL KINDS 
CATALOGUES ON APPLICATION 
C. F. CASELLA & CO., Ltd. 
Wansey Street Works, Walworth, London, S.E. 
