Marcu 25, 1897 | 
NATURE 
497 
Prof. Hughes’ rooms. 
contemporary (March 6), ‘* besides the professor, there were 
present the late Prof. Huxley, Prof. Norman Lockyer, Mr. W. 
H. Preece, Mr. Conrad W. Cooke, and Mr. Perry F. Nursey. 
It is an idiosynerasy with Prof. Hughes that his remarkable in- 
ventions have all been worked out with the most simple and 
commonplace tools. Thus on the occasion referred to the 
apparatus was of the most primitive character, and, with the 
exception of a Bell telephone receiver, could not be appraised at 
more than a few pence. This apparatus had a child’s halfpenny 
wooden money-box for a resonator, on which was fixed by 
means of sealing-wax a short glass tube, filled with a mixture of 
tin and zine, the ends being stopped by two pieces of charcoal to 
which were attached wires, having a battery of three small 
Daniell cells—consisting of three small jam-pots—in circuit. 
The wires were led away toa Bell telephone placed in an ad- 
joining apartment. The money-box, which had one end 
knocked out, served asa mouthpiece or transmitter, while a Bell 
telephone was used as a receiver. Sounds scarcely audible, and 
some absolutely inaudible, to the unassisted ear, were by means 
of this apparatus delivered with startling loudness through the 
Bell telephone. Numerous experiments of the utmost im- 
portance to physicists were carried out by Prof. Hughes with 
this apparatus, and with modifications of it, all proving that he 
had succeeded in producing the simplest and most powerful 
electric articulating telephone ever known.” The first public 
demonstration of the sensitiveness of the instrument took place 
at the Royal Society on May 8, 1878. 
THE Royal Meteorological Society has for many years past 
held an exhibition annually, which has been devoted to some 
special class of meteorological instruments. This year an exhi- 
bition of meteorological instruments in use in 1837 and 1897 was 
arranged, in commemoration of the Diamond Jubilee of H.M. 
the Queen. The exhibition closed on Friday last. The instru- 
ments which were in use in 1837, as might be supposed, were 
not very numerous, but many of them were somewhat quaint 
and of great interest. Sir E. H. Verney, Bart., showed an old 
barometer with a large spirit thermometer, which latter had an 
arbitrary scale decreasing as the temperature increases, ‘‘ex- 
tream cold*’ being 90° and ‘‘ extream hot” o°. The instruments 
in use during 1897 were, however, very numerous, and com- 
prised various forms of barometers, thermometers, hygrometers, 
rain-gauges, anemometers. nephoscopes, sunshine recorders, 
actinometers, aneroids, electrical and miscellaneous instruments. 
Many of the instruments were self-recording, and were shown in 
action. The most interesting exhibit was a railed-off enclosure 
representing a typical climatological station of the Royal 
Meteorological Society. This included a Stevenson thermometer 
screen, fitted with dry bulb, wet bulb, maximum and minimum 
thermometers ; rain-gauge ; solar and terrestrial radiation ther- 
mometers; sunshine recorder, and earth thermometer ; all of 
which were placed zz sit. The exhibition also included a 
number of charts and photographs of great interest, particularly 
those by Mr. J. Leadbeater, of ice crystals on window-panes. 
Mr. W. H. Dines showed an experiment illustrating the forma- 
tion of the tornado cloud, and Mr. Birt Acres exhibited some 
exceedingly interesting studies of form and movement of clouds 
and waves projected on the screen by his kinematoscope. 
Tue Mond gas-producer plant and its application, was the sub- 
ject of a paper read by Mr. H. A. Humphrey at the Institution of 
Civil Engineers on March 16. The advantages of gaseous over 
solid fuel have led to an increasing demand for gas-producers to 
convert the solid fuel into the gaseous state. Gas-producers have 
‘hitherto been constructed to make gas with little regard to by- 
products, and none have been made to give good results with 
cheap slack coal, and where the use of gas for gas-engines has 
NQ. 1430, VOL. 55 | 
“Upon that occasion,” remarks our | 
been concerned only expensive fuel, such as anthracite or coke, 
have been found available. But the Mond producer and re- 
covery plant, described by Mr. Humphrey, not only employs 
cheap bituminous fuel, but recovers from it go lbs. of sulphate 
of ammonia per ton, and yields a gas eminently suitable for use 
in gas-engines and applicable to all cases of furnace work. The 
difficulties to be overcome before bituminous slack could be 
utilised in producers were many; nevertheless Dr. Ludwig 
Mond has not only succeeded in overcoming them, but has ad- 
vanced the subject another stage by recovering as ammonia 70 
per cent. of the original nitrogen contained in the fuel. The 
distinguishing features of the Mond process were enumerated, 
and the manner in which the plant is worked was described in 
detail. 
STATISTICS of the United States Patent Office, just published, 
show an increase of about 3000 in the number of patents taken 
out during the last year compared with the year before. The 
surplus fund of revenues above expenses of the office now exceeds 
four million dollars. 
REFERRING to our note on Prof. F. Plateau’s experiments 
on the mode in which insects are attracted to flowers, Mr. G. 
W. Bulman calls our attention to a paper by him in the Zoo- 
Jogist (vol. xiv. 3rd series, p. 422), and to others published in 
Sctence Gossip between 1888 and 1892, in which he arrived at a 
conclusion similar to that of Prof. Plateau, viz. that the bright 
colour of the corolla does not act as a beacon to attract insects. 
WE have received the first part of the division, ‘‘ Aves,” of the 
great new German zoological work, called ‘‘ Das Tierreich,’” 
which is proposed to contain a descriptive synopsis of all the 
recent forms in the animal kingdom. The general editor of the 
whole work (on behalf of the German Zoological Society) is Dr, 
F. E. Schulze, of Berlin. The editor of the ‘‘ Aves” is Dr. A. 
Reichenow, but the present part of that division has been pre- 
pared by Mr. Ernst Hartert, director of the Zoological Museum 
of Tring. There can be no doubt as to the merit of Mr. 
Hartert’s work, which gives all that should be contained in such 
a synopsis, and no more. But it is a misfortune that German 
patriotism has rendered it necessary to use German instead of 
Latin in such a work, which is of a cosmopolitan nature. 
Multitudes of English and American zoologists, we regret to say, 
are still unable to read German with any sort of facility, while 
every one who has been to school understands a little Latin. 
ABOUT two years ago Zelinsky found that two hydrocarbons 
could be obtained from hexamethylene iodide by reduction, the 
product prepared by means of zinc and hydrochloric acid being 
different from that got when hydriodic acid was used. Further 
experiments, of which an account is given in the current number 
of the Berichte, have convinced him that the first of these is the 
true hexamethylene; whilst the second is identical with the 
methylpentamethylene, which was first prepared by W. H. 
Perkin, jun., and P. Freer. The hexamethylene ring, therefore, 
under the influence of hydriodic acid at 230° changes into a more 
stable isomeric form. The nature of this change is quite in 
agreement with Baeyer’s celebrated ‘‘ tension-theory,” according 
to which the pentamethylene ring is more stable than any other. 
It appears probable, moreover, that the hexahydrobenzene 
which is formed by the action of hydriodic acid on benzene, and 
which has long passed for hexamethylene, is in reality methyl- 
pentamethylene. 
TuE additions to the Zoological Society’s Gardens during the 
past week include two Vulpine Phalangers (Trichosurus vulpe- 
cula, 8 @) from Australia, presented by Mr. W. H. Stather 
two Muscovy Ducks (Caérzna moschata,? 9) from South 
