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Noting the direction of the wind is part of the regular routine of observations at the Observatory on the summit of Ben Nevis. Owing to the frequency of frozen fogs in winter, anemometers are practically useless, but the record is made complete enough for many purposes by the hourly observations; at each hour of the day and night the wind, at the time of making the observation, is noted, and the number of entries of each wind direction in the day, month, or year must very nearly represent the relative frequency of such winds for that time. Table I. is a summary giving the number of times each wind is observed in each month of the year on an average of six years (1884–89) expressed in percentages; thus in January, out of the 744 hours of the month, there are 120 hours or 16·1 per cent, of N. wind. For the year the most frequent wind is N., next come S.W., S.E., and S., all about equal, and the least frequent is E. N. is the point of greatest frequency in all months except May, when S.E. takes its place; in May 1889 there were only 15 hours in the whole month with N., N.W., or N.E. winds, and during three-fourths of that month the air was moving from the S. or S.E. This was, of course, an exceptional month, but in the six years there are only two (1887–88) in which N. was the most frequent wind in May.

The quasi-periodic 27-day variations ƒ 0 E at Washington are significantly related to corresponding variations of the sunspot number.

Critique of paper on water crystal existence on Venus, presenting arguments against existence of clouds of micron sized ice crystals

companying figure. The 28.4-3, surface field calculated by RING is within 13% of 32.4-3, field predicted using Sckopke's relation and an equatorial dipole field of 0.31 gauss. This correction decreased the magnetic moment of the quietday ring current from 0.26 M• to 0.21 Ms, 86% of which is contained by the low-energy protons (E _( 50 key). On this basis the subsolar magnetic field would be decreased by 4%, and the required solar wind density would be decreased by about 8%. However, this correction also increased the size of the nondipolar component near 11 R• to more than 10% of the dipole field. In summary, these small offsetting changes

Dear Sir, I regret that in my paper on the “Diurnal Variations of the Wind and Barometric Pressure,” published in vol. xxv, p. 402, of the “Proceedings of the Royal Society,” I have inadvertently referred the Bermuda wind observations to civil time instead of to astronomical time. The correction of this error shows that the variation of the values of the hourly inequalities of the wind components at Bermuda is very much less during the hours when the sun is above the horizon than during, those when he is below it, especially in the winter half year.

In this Journal Bowen (1953) has recently put forward evidence purporting to show that " there is a marked tendency for heavy falls of rain to occur on certain days rather than on others, and for this pattern to be repeated year after year". It is claimed that these days of heavy rain coincide (within a margin of variation of �2 days) in many parts of the world, and a theory is put forward explaining the supposed phenomenon in terms of world-wide concentrations of dust produced by the impact of known meteor showers on the atmosphere. He suggests that debris from these meteors, partially disintegrated by atmospheric friction at heights of about 100 km, filters down to the tropopause in about 29 days, where it activates or " seeds" rain clouds, so producing heavy rainfall.

The rate of deposition of particles to smooth extended surfaces and horizontal filter paper has been measured in a large wind tunnel. The particles used covered the size range from 0·08 to 30 μm and the effect of wind speed was also investigated. The results provide some confirmation of theoretical predictions for deposition rates to smooth surfaces and they have also been used to evaluate the performance of a dry deposition sampler, made from filter paper, which has been used to sample the natural aerosol.

The Direct-Flow Sampler is an improved balloon-borne device designed to collect particulate matter from very large volumes of stratospheric air at altitudes between 50,000 and 100,000 ft. This equipment utilizes a high-volume blower to pull air through 1 sq ft of Institute of Paper Chemistry (IPC) #1478 filter paper at rates from 400 to 800 cfm. Laboratory tests at low pressures involving aerosols of known size and density, together with intercomparison flights with other sampling devices, indicate that the Direct-Flow Sampler is a very efficient collector of submicron particles. Several vertical profiles of radioactivity over Minneapolis, Minn., that were obtained with impactor collectors and with filter samplers are shown to be in generally good agreement. Development of this sampler was supported by the Atomic Energy Commission as part of a program aimed at achieving a better understanding of the characteristics of stratospheric dust and radioactive debris, and of the mechanisms controlling fa...

The instrument described gives a continuous record on photographic paper of the change in weight of a naturally exposed grass surface, 330 cm2 in area. The sensitivity is 2 mg cm−1 per cm of record and the time scale is 0.5 hr/cm. Observations suggest that on very calm nights the condensation of vapour reaching the surface by diffusion from the atmosphere is only a small fraction of the total ‘dew.’ The maximum rate of deposition that has been observed on short grass is 0.03 mm hr−1.

Measurements of liquid-water content in cumulus clouds were made with a device which records changes of conductivity of a paper tape with changes of wetness. One series of measurements was made in tropical cumuli; another was made in clouds over the Central United States. Examples of the variability of liquid water in convective clouds and typical values are given. It was found that the high values of liquid-water content occurred in clouds in which precipitation formed. Comparisons of the observed values of liquid water with theoretical values based on an assumption of moist-adiabatic air ascent, without mixing, lead to the conclusion that clouds with precipitation contain regions where the liquid water exceeds the theoretical amounts.

The previous paper of this series contains a study of the respiration of a set of 21 apples brought from cold storage at 2·5°C. and examined in the laboratory at 22°C. The complex phenomena presented by the respiration while in a current of ordinary air were alone dealt with in that paper, but these same individual apples were also investigated in nitrogen and in various percentages of oxygen. In the present paper the respiration data obtained in nitrogen are to be examined, while a subsequent paper will take up the phenomena presented in concentrations of oxygen. The complexities of CO 2 -production in nitrogen are no less than those already studied in air, though they bring us into a new field in which the oxidation factor is excluded. The behaviour of a number of individual apples alternately in air and nitrogen is recorded by long series of continuous observations, and these call for detailed analysis.

At the end of his paper on the long period tides Hough* discussed the effects of precipitation and evaporation in reference to steady currents in the ocean. He assumed that the ocean covered the whole globe and that the precipitation and evaporation were functions of the latitude only. His work showed that no steady motions exist in this case. The present paper examines the case of an ocean bounded by shores extending from pole to pole along meridians, for which the evaporation and precipitation are also functions of the longitude. The results show that for a probable system of distribution of evaporation and precipitation steady currents do exist and are of the kind actually observed in the great oceans.

In a previous paper it has been shown that the temperature of the air above 60 km., as calculated from meteor observations, is much higher than that between, say, 10 and 50 km., and is probably about 300° A. It appears that the only explanation of the high temperature is that the air absorbs an appreciable amount of sun's radiation in addition to earth's radiation. If this is so, one might expect a large change in temperature between summer and winter.—a change greater than that which occurs, say, in tbs stratosphere, viz., about 6°. The object of this note is to examine whether it is possible to kind evidence of this change of temperature. If so, it is confirmation of the previous result, that the temperature at great heights is above that of the stratosphere. Unfortunately, the main method used in calculating the actual density in the previous paper involves the cube of the meteor's velocity, and the velocity, as measured by eye observations, is necessarily very inaccurate. Thus the errors of observation mask any small difference in density of the order of magnitude which might be expected. There are, however, live other possible eases in which a difference between summer and winter might be shown, but in most of those the effect expected is very small:— (1) As the temperature of the compressed gas in front of the meteor is proportional to the initial temperature of the air, one might expect the minimum velocity at which meteors can appear to be greater in winter than in summer. The results of eye observations are not sufficiently accurate to show this difference.

In a paper published in the ‘Philosophical Magazine’ of May, 1913, an account is given of some experiments which show that the raising of a cloud of dust is accompanied by the production of a large amount of electricity. The dust was usually blown away from the surface of a Hat piece of material or from the end of a tube. Large quantities of electricity were produced by this means and the sign of the charge seemed to depend upon the nature of the material used to form the dust cloud. Basic bodies generally acquired a negative charge, and acidic bodies a positive charge. It might be suggested that the origin of the charges lay in the friction of the particles of material against the surface from which they were blown, but this, however, is not altogether the case, as the following experiment will show. An insulated brass tube, 25 cm. in length and 1·5 cm. in diameter, was connected to an electroscope. Tubes of different materials and of a slightly smaller diameter were provided to fit inside it so that the nature of the surface from which the dust was blown could be varied. Under these circumstances it might be expected that the charge carried away by the dust, and also that retained by the tube, would vary with the nature of the surface, but this was not the case, for with the same substance for creating the dust, the electrification was always the same no matter what was the nature of the surface from which it was blown. For example, sand always furnished a positive charge and red lead a negative one, and other materials gave charges of the signs given in the paper referred to. Again, the nature of the surface against which the dust was projected was also without influence upon the charge acquired. Clouds of dust were raised by blowing a current of air through the dust contained in a small wash-bottle, and the cloud projected against an insulated plate connected to an electroscope. The charge gained by the plate was of the same sign whether the plate was rough or smooth, or coated with different materials, so that it appears evident that the charge is actually produced upon the dust cloud itself. It has been shown that the charge upon the dust is apparently accompanied by one of opposite sign upon the air, and a convenient arrangement for showing the presence of these two charges is given in fig. 1. The dust raised by blowing air through W is projected against the wire gauze screen G and the greater portion is caught, but the air accompanying the dust is carried on. At some distance (50-100 cm.) behind the gauze a small radium-coated plate E served to collect any charge present upon the air. Electroscopes E 2 and E 1 indicate the charges acquired by G and R. A few typical cases are given in Table I.

A graphical method of calculating the radiative equilibrium temperature of the upper regions of the atmosphere, taking into account the variation of absorption with wave-length, has already been described in detail.* The equation of radiative equilibrium is most simply written in the form: 2 ∫ 0 ∞ K λ B λT 0 d λ = ∫ 0 ∞ K λ (S λ + E λ + A λ ) d λ, where, for any arbitrary layer, K λ is the absorption, B λT 0 is the black body radiation at temperature T 0 degrees absolute, S λ , E λ , and A λ are respectively the solar, terrestrial, and atmospheric radiations reaching the layer, all at wave-length λ. On account of the irregular variations of K λ the integrations can only be performed graphically, and one cannot solve directly for the temperature. The term A λ for any layer depends on the temperatures of all the other layers of the stratosphere, and unfortunately it is much too large to be neglected. Therefore it is evident that the process of determining the temperature distribution with height has to be one of successive approximation. On the basis of an assumed temperature distribution the terms of the equation are calculated. The total of the right-hand side then gives the energy that must be radiated by any layer. In general this is not equal to the radiation shown by the left-hand side for the assumed temperature. By calculating the left hand side for various other temperatures and plotting a curve, an estimate may be made of how near the agreement is. This serves as a guide in making a fresh assumption of the temperature distribution in order to start again. Such a process is continued until satisfactory agreement between assumed and calculated values is reached for all layers. At the end of the first paper it was concluded that, given the layer of ozone, a theoretical consideration of an assumed condition of radiative equilibrium for water vapour and ozone, under solar and terrestrial radiation, indicates the existence of a warm region above 40 km. In this paper the work is carried much further, various changes in fundamental assumptions are tested, and the effects of some varying physical conditions are calculated.

The method employed is essentially that described in my paper “On a Method of Studying Transpiration,” where it was applied to the investigation of the relation between the relative humidity of the air and the loss of water by leaves. The stomata of the plants used were closed by vaseline or cocoa-fat rubbed in, and the leaves were then incised to allow of transpiration. No attempt was made to subject the plants to light of known intensity. My object was to compare the transpiration occurring in a dark room with that in a north light at a laboratory window. The rates of transpiration were estimated either by weighing or by means of a potometer, and the general plan was to subject the plant to alternate light and dark periods of something like an hour. The psychrometric condition of the laboratory air and that of the dark room was estimated by the wet and dry bulb thermometer, and the transpiration rates corrected for any differences, in the manner described in the paper above referred to. The first experiment was made by a plan which has some merits, but was afterwards replaced by the simpler method of moving the apparatus from the window to dark room and back again to the light.

1. The water which falls as rain is originally evaporated either from land surfaces, forests, etc., or from the oceans, in particular from the latter. It is therefore of importance to ascertain how the evaporated water distributes itself in an atmospheric current during its progress across a water surface, and, further, to investigate the relation between the length of the path over the water surface and the amount of water thereby rendered available. In this paper, these problems are treated for the case of a current of air of uniform speed moving over a water surface of uniform temperature. An empirical formula is employed to represent the rate of evaporation from each element of the water surface, and account is taken of the stirring upwards of the evaporated water by the agency of turbulence, assuming the latter to be uniformly distributed throughout the current of air. The results obtained would find application, for example, in discussing problems connected with evaporation in the trade wind zones, or from inland seas and lakes, or, in particular, from the North Sea, winds from which frequently bring much cloud and quite appreciable rainfall to the eastern coasts of Great Britain and the northern coasts of France. All the constants occurring in the formulae obtained are known, either accurately or approximately, and, accordingly, the order of magnitude of the evaporation from a given stretch of water, under assigned conditions, can be estimated. What is also of importance, is the comparison of the amount of water evaporated from a given area or of the distribution of water vapour in the air above it, under one set of conditions, with those under a different set. Of particular interest is the effect of varying the speed of the air. 2. The suggestion which led to the present investigation is contained in a paper on “ The Meteorological Conditions of an Ice Sheet and their bearing on the Desiccation of the Globe.” The author of that paper, in considering the evaporation in tropical and sub-tropical regions during the Quaternary Ice Age as compared with that at the present time, has occasion to compare the rate of evaporation from large expanses of water under different conditions as to wind and surface temperature, and Lt. -Col. E. Gold, in the discussion, emphasises the fact that this is in reality a very complex problem for the formula used (quoted below, p. 474) for the rate of evaporation from an element of the surface, involves the vapour pressure at the dew point of the air “ near ” the surface. Now this vapour pressure varies from point to point along the current of air which is traversing the water, so that an integration is necessary in order to obtain the rate of evaporation from a large stretch of water, and, further, the vapour pressure at any point depends on the speed with which the air has reached that point, which complicates the problem of comparing the evaporation under different wind conditions.