June 27, 1895J 



NATURE 



209 



chemical nature, cleanness, and dust) upon the deposition of 

 dew and the determination of the dew-point. 



(4) The ))ehaviour of the wet-bulb thermometer, when covered 

 with water, in an atmosphere of water vapour and of ice vapour. 



(51 The influence of radiant heat on wet bulbs covered with 

 ice or water. 



(6) The increase of the reading of the wet-bulb thermometer 

 due to any compression that may result from the formation of 

 the ice film on the muslin covering ; its dependence on the 

 muslin rather than on the ice. 



(7) The determination of the tension of water vapour and ice 

 vapour at and below freezing. 



(8) The rate of iliffusion of ice vapour as distinguished from 

 aqueous vapour, and also the rates of evaporation from ice and 

 water at the same tem]>erature. 



(9) The condensation of vapour in a region free from solid 

 nuclei, and after the temperature has been reduced to, or below, 

 the point of saturation so that the vapour is in a state of unstable 

 equilibrium. 



! 10) The change that can be produced in the pressure and 

 temperature of a confined volume of dust free " dry saturated " 

 steam or other vapour by the introduction of dust particles 

 having various chemical and physical properties. This is the 

 secret of the action of the "cloud engine ' of Montgomery J. 

 Storms. 



(11) Invention tif improved and practical methods ,:)f obtaining 

 the moisture contents of the air — especially at low temperatures. 

 — C. F. .M. 



(12) Invention of recording thermometers, barometers, and 

 hygrometers adapted by their accuracy, their extreme lightness, 

 and the quickness with which they respond to atmospheric 

 changes, to be carried up by balloons and by kites in investiga- 

 tions into the condition of the higher atmosphere. — C. F. M. 



(13) The development and perfecting of the art of constructing 

 and tlying kites with a view of rendering this practically applicable 

 in investigations of the condition of the atmosphere at moderate 

 elevations. — C. F. .M. 



(14) Invention of improved and practical devices for the 

 registration of sunshine and cloudiness, both day and night. — 

 C. F. M. 



(15) Invention of devices recording exactly the beginnings and 

 endings, amounts and rates, of precipitation, &c. — C. F. M. 



(16) F.\plan;Uion of the formation of ice-needles in gravelly 

 soil, and determination t)f the amount of heat x-\\ moisture 

 retained at the earth's surface by this formation. 



(17) Explanation of the origin of the hollow tubes in the ice- 

 needles anil the similar hollow tubes in snow crystals and the 

 analogous holes in hailslt>nes. 



(18) The connection between atmospheric conditions and the 

 formation of snow crystals of different shapes and sizes. 



I19I The radiating and conducting powers of layers of snow 

 freshly fallen or old and granulated. 



(20) The radiation and absorption of heat by dustless, dry 

 air, and also by ordinary atmospheric air containing dust and 

 vapour or ice particles. 



(21) Investigation of the formula for computing the velocity 

 and the pressure of the wind from various forms of anemometers, 

 especially the whirling, the pressure, and the suction anemo- 

 meters. 



(22) Invention of the most convenient and cheapest form 

 of nephoscope for determining either direction or velocity, or 

 both these elements of the motion of the clouds. I 



(23) Investigation of the correction to be made to the record 

 of the ordinary cylindrical rain and snow gauge for the effect of 

 the wind in drifting the rain, an<l especially the snow. 



(24) Study of the temperature of the soil at ditVereiU depths 

 from the surface-layer down to three feet and under different 

 conditions, as to moisture-content, sunshine, and wind. 



(25) Invention of better metho<lsof determining at any moment 

 the temperature and moisture at any depth in the soil. 



(26) Determination of the quantity of water evaporated from ' 

 natural surfaces, especially ocean water, ice or snow, fresh water, 

 and forests or cultivated fields, and its relation to humidity, 

 temperature, and wind. 



(27) Improvements in the actinometer and a series of deter- 

 minations of the amounts of heat received at any point, both 

 from the sun directly and from the clouds and the atmosphere by 

 reflection or radiation. 



(28) Observations of the polarisation and the intensity of blue 

 sky light and comjiarison with o|rtical theories. 



(29) Instrumental methods for recording some of the various 

 chemical effects directly produced by solar radiation, and which 

 are of special importance in the growth of plants, the decomposi- 

 tion of the soil, and the purification of water. 



(30) .A series of determinations or, still better, a continuous 

 record of the simultaneous differences of electric jwtential 

 between the earths surface, and several points in the free 

 atmosphere, one hundre<l feet apart, vertically, meridionally, 

 and prime-vertically. 



(31) A similar series for several points beneath the earth's 

 surface as to their electro-magnetic condition, and a correlation 

 of the distribution of electric conditions with the electric currents 

 in the air and the earth. 



(32) A study of the scintillation of the stars and its relation 

 to atmospheric conditions. 



(il)^ ^ study of the ap|>arent acoustic opacity of the atmosphere 

 at certain places and times. 



(34I An explanation of the sounds attending large aerolites, 

 and an explanation as to what may be learned therefrom regard- 

 ing the upper atmosphere and in regard to the improvement of 

 fog signals. 



(35) A study of the formation of halos, parhelia, .and corona, 

 by the action of snow crystals and water-drops on sunlight. 



(36) Investigation of the first step in the process of convection, 

 as it occurs in the free atmosphere by which small currents of 

 warm air, rising as slender rolls and whirls, mix with the cooler 

 air, and are broken uj> within a few feet of the earth's surface ; 

 a tletermination of the limit at which such convection becomes 

 inappreciable. 



(37) A study of the larger convection currents, their relation 

 to the horizontal motion, the extent to which they retard and 

 accelerate the motions or increxse and tlecrease the pressures in 

 the upper and lower strata. 



THE SENSES OF IXSECTS} 



/^F the five ordinary senses recognised in ourselves .ind most 

 ^■^ higher animals, insects have, beyond all doubt, the sense 

 of sight, and there can be as little question that they possess the 

 senses of touch, taste, smell, and hearing. Vet, save perhaps 

 that of touch, none of these senses, as possessed by insects, can 

 be strictly compared with cjur own, while there is the best of 

 evidence that insects possess other senses which we do not, and 

 that they have sense organs w ilh which we have none to compare. 

 He who tries to comprehend the mech.anism of our own senses — 

 the manner in which the subtler sensiitions are conveyed to the 

 brain — will realise how little we know thereof after all that has 

 been w ritten. It is not to be wondered at, therefore, that authors 

 should differ as to the nature of many of the sense organs of 

 insects, or that there should be little or no absolute knowledge 

 of the manner in which the senses act upon them. The solution 

 of psychical j^roblems may never, indeed, be obtained, so 

 infinitely minute are the ultimate atoms of matter ; and those 

 who have given most attention to the subject must echo the 

 sentiment of Lubbock, that the princiixtl impression which the 

 more recent works on the intelligence and senses of animals 

 leave on the mind is that we know very little, indeed, on the 

 subject. We can but empirically observe and experiment and 

 draw conclusions from well attested results. 



Sight. — Taking first the sense of sight, much has been written 

 as to the picture which the compound eye of insects pro<luccs 

 upon the brain or upon the nerve centres. -Most insects which 

 undergo complete metamorphoses possess in their adolescent 

 states simple eyes or ocelli, and sometimes groups of them of 

 varying size and in varying situations. It is difficult, if not 

 impossible, to demonstrate experimentally their efliciency as 

 organs of sight : the iirobabilities are that they give but the 

 faintest impressions, but otherwise act as do our own. The fact 

 that they are |X)ssessed only by larvx- which are exposed more or 

 less fully to the light, while those larva* which are endophytous, 

 or otherwise hidden fnuu light, generally lack them, is in itself 

 proof that they ]>erf()rm the ()rtlinary functions of sight, however 

 low in degree. In the imago state the great majority of insects 

 have their simple eyes in addition to the compound eyes. In 

 many cases, however, the former are more or less covered with 

 vestiture, which is another evidence that their function is of a low 



I From an address on " Social Insects," delivered by Prof. C. V. ^ilcy, as 

 President of tlic Rtological Society of Wasliinglon. (Reprinted (sliglitly 

 condensed) from Insect Life. vol. vii. No. I.") 



NO. 1339, VOL. 52] 



