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Magnitude estimations of saturation were obtained for each of 15 pigmented surfaces of different hue, viewed under artificial light in a 4° test field. Saturation was found to be related to colorimetric purity by a power function whose exponent varied with the dominant wavelength. The highest exponents were in the yellow-orange region and the lowest in the blues. Five of the color samples were viewed under both daylight and artificial light with test fields of 4° and 0.7°. The larger visual field and daylight gave somewhat lower exponents for all dominant wavelengths except those in the yellow region. The exponents for saturation of surface colors are systematically higher than those reported for aperture colors.

The migratory behavior of American shad (Alosa sapidissima) approaching their natal river during the final saltwater stage of the spawning migration was studied using ultrasonic tracking and conventional tagging procedures. Initial displacement of most sonic-tagged shad released without displacement adjacent to and 10 km west of the Connecticut River was not in the direction of the home river. These fish, however, homed successfully to the Connecticut River as did dart-tagged shad released in the same areas.Shad exhibited two major behavior patterns; countercurrent orientation in response to the reversing tidal current and adjustment of swimming speed to changes in tidal velocity. Countercurrent orientation was equally significant during daylight and darkness, whereas the adjustment of swimming speeds to tidal current velocity was more significant during daylight than darkness.Shad tracked to the west exhibited a westerly bias inherent in the basic open water behavior patterns. Shad exhibited a greater degree of directed movement when oriented against the ebb tide and adjusted their swimming speeds to exceed the ebb tide velocity and to approximately equal the flood tide velocity. Shad tracked to the east exhibited the same major behavior patterns but with the opposite directional bias.A hypothesis is presented suggesting that the location of the home river is achieved by means of a nonrandom search. Environmental clues indicative of the Connecticut River act to establish a preferred direction of displacement while the actual unidirectional displacement is achieved by reference to the rate and direction of tidal currents.

Data on the migratory behaviour of salmonids were collected at a gauging weir by means of a restivity fish-counter which triggered a motor-driven 35 mm still camera to provide photographic records of passing fish. A clear bimodal seasonal pattern of movement was observed in three consecutive years with peaks during June–August and October–December. Daily variations in the rate of movement could not be correlated with changes in discharge or temperature. Salmonids tended to move at discharges lower than those generally available. This contrasts with other published work and was attributed to the more equitable flow-pattern of chalk rivers. There was no optimal temperature associated with movements. Some evidence suggested that the largest fish moved earlier in the year but this was not marked. In clear water most movement occurred during the hours of darkness but during floods, when the river was turbid, the diurnal pattern tended to be reversed with greatest movement during the hours of daylight. Most fish negotiated the weir close to the bottom, well below mean velocity, and took a central path through the flume. Although analysis of upstream migratory behaviour was hindered by the lack of data on the numbers of fish available below the counting point it was concluded that the basic pattern of migration is established by time (season). Changes in discharge, light intensity and other parameters may then play a secondary role in modifying the details of the pattern but attention is drawn to records of movements in regulated flows where a remarkably constant pattern is shown from year to year.

Data are provided for the extraterrestrial radiation of the Sun, also for those quantities which are of interest to the illuminating engineer, namely luminance distribution, zenith luminance, illumination, spectral distribution and luminous efficacy of the overcast sky, clear sky and sunlight. Formulae for luminance and illuminance due to several authors are given and shown graphically. CIE recommendations are included.

Since the proposed index to rate the color rendering properties of light sources, there has been a desire on the part of many individuals, especially those concerned with marketing lamps, to put this on an absolute basis. This would allow all lamps to be rated on the same base line thus allowing, for example, the direct comparison of the color rendering properties of a warm white and a daylight lamp. In this paper a method of doing this is presented, followed by the reasons why this serves no useful purpose.

Four fluorescent lamps of daylight chromaticity, and with varying Color-Preference Index (CPI), illuminated an array of fruit, vegetables, breads and meat. The lamps were rated in order of preference for the coloration of this array by 267 observers. Excellent correlation of observer preference with CPI, as well as with the prime-color content of the spectral power distributions of the lamps, served to validate the CPI and Judd's assignment of preferred chromaticities of identifiable objects.

Four hundred and forty vent-sexed commercial broiler chicks were used in this study. One half of this sample was exposed to common fluorescent light, the other half to a light source that in the spectral composition better approximates daylight characteristics (Vita-lite). Body weights of all birds were measured at weekly intervals. Weight of the body organs was measured on 20 birds randomly taken from each of four possible light source-sex combinations at 14-day intervals. The only significant difference in body weights linked with lighting was found in 2-wk-old chicks. High interactions between sex and lighting at this age revealed a positive effect of Vita-lite on females. In all other age categories, lighting did not affect body weights and did not interact with sex. Regression of body weights on age did not show any differentiation in growth related to the light source. Proportional weight of body organs did not indicate any significant effect of lighting. Birds in cages, illuminated with Vita-lite, when transferred to floor pens showed lower ambulatory activity than their counterparts from normal fluorescent light. Overall mortality during the first 14 days was lower in the Vita-lite group. Frequencies of subjective classifications of birds’ visual appearance showed evident sex × light source interactions only at the age of 14 days.

Continuous time series records of numbers of fish ascending a Denil-type fishway on the Annaquatucket River, North Kingstown, R.I., were obtained with a Smith-Root electronic fish counter during 1971 and 1972 spawning migrations. Seasonal trends in numbers of fish counted per day were unimodal and showed similar time patterns in both years. Water temperatures delimited the seasonal migration period. Short-term fluctuations in fish movement showed a significant zero-lag positive correlation with fluctuations in water temperature and a significant positive correlation with fluctuations in volume outflow when lagged 2 days behind outflow. A 10–14-day cycle appeared in fish migration data. Light intensity determined when alewife (Alosa pseudoharengus) movement would occur during a 24-h period, whereas water temperature controlled the pattern of movement exhibited during daylight hours. Fish responded to hourly water temperatures on the basis of their value relative to a changing baseline temperature.

The building the birds nested in was on an abandoned farmstead about a mile from a public road. It had log sides and a metal roof and was formerly used for a tobacco packing shed. With the hope that birds could be induced to use it for roosting or nesting, I left an upper window open and removed some of the loft floor to give them access to the ground floor. There were no other windows in that part of the building. I divided a back room on the ground floor into two compartments by installing a canvas partition, with the only route of access to one part through the loft floor, and spread several bucketsfull of sawdust on the floor in a corner of this part of the room as a possible nesting attraction. I entered the other part of the room by walking through two ground floor rooms from outside the building. I watched the nesting vultures through a hole in the canvas as I sat on a chair less than 3 m from them, sometimes much less. I tried to study the pair's nest life with a minimum of disturbance; thus I hesitated to catch the birds for banding during incubation. Rather I tried to find a method to mark them without capture. At the crucial time one of the birds came to the nest marked with white spots on its mantle, presumably excreta caught while roosting beneath others. The bird retained these markings until the next heavy rainfall 11 days later. When the young vultures were 24 days old, I finally caught and banded one of the parent birds. I spent all the daylight hours of 25 days at the nest and parts of 28 additional days. I slept in the building on 11 different nights.

Throughout history daylighting has been a crucial factor in the design buildings. Until this century windows have held a special place in architecture. The effects of locational differences and the controls devised to vary the admission of light are discussed. The relationship between the functional needs of people or processes and the adequacy of light are considered in terms of architectural form. Lighting can be strongly evocative and the way it is used can reinforce philosophical ideas which may be implicit in the expression of a building. The spacing and height of groups of buildings also have a bearing on the problem and are discussed. It is concluded that though it is becoming increasingly difficult to provide the illuminances required for many activities by the use of daylight alone, qualities such as visual relief, contact with the outside world, sunlight and the pleasing effects of modelling associated with daylight must be taken into account.

Drifting invertebrates were collected hourly during 24-hour sampling periods at two stations in the Snake River. The greatest number of invertebrates was collected on 8 and 15 July 1966 at station 1 between 9:00 p. m. and 12 midnight, then the numbers gradually decreased until the low daylight drift rate was reached at dawn. On 26 and 27 August 1966 at station 2, the diel periodicities of drifting invertebrates were different than at station 1. Many species increased their drift rates slightly during the first hour of darkness but also exhibited a higher drift peak later in the night.

Even if commercial products such as automobile paint and upholstery match in color and lightness under daylight illumination, they often mismatch under some of the many other common illuminants. Both paint and upholstery possess a spectral reflectance curve with a per cent of light reflected at each wavelength through the visible spectrum. Reflectance differences in certain particular wavelength regions are the troublemakers in such a mismatch. New fluorescent lamps emit in these wavelength regions. By causing about the worst possible mismatch, the new lamps give a dependable estimate of potential trouble with matching colors, and can indicate where the trouble lies. Conversely, prime-color fluorescent lamps have the peculiar capability of preserving a match prepared in daylight.

The Es-echo phase path records on 5.6 MHz have shown that the bottom surface of the Es was sometimes very sharply bounded. Some evidence showing that the formation of Es is a highly localized phenomenon has been obtained. The phase path variations of ‘O’ and ‘X’ components in the F2-region echo during the formation of Es showed that the increase in the ionization in the Es is not totally from a vertical redistribution of the ionization along the ray paths. From spaced phase path records of Es echoes taken during the daylight hours, apparent drift speeds in the range 40–130 m/sec with an eastward sense of the east-west components of Es apparent drifts were observed. This is opposite to the sense of the east-west components of E-region drifts during the daylight hours but is the same as that during the nighttime hours. An attempt is made to interpret these observations.

The daily energy expenditure of Yemenite and Kurdish Jews has been assessed in summer and winter. The majority of the male subjects were engaged in farming; the women were mainly housewives. A timed activity survey was carried out on all subjects. The differences between summer and winter were, in general, small and the time spent by the men in different activities averaged for the two seasons were, for the Yemenite Jews 7.69 h lying, 7.16 h sitting, 7.6 h working. The Kurdish Jews spent 8.44 h lying, 6.4 h sitting and 7.4 h working. Energy expenditure was computed from the timed activity survey and measurements of oxygen consumption in a number of tasks. The energy expenditure of the men in the summer was 3 050 kcal (12760 kj) per day for both the Yemenite and the Kurdish Jews. In the winter, the Yemenite Jews expended 3000 kcal (12560 kj) and the Kurdish Jews 3110 kcal (13020 kj) per day. The Yemenite Jewish women expended 2280 kcal (9550 kj) per day in the summer and 2400 kcal (10040 kj) per day in the winter, and the Kurdish Jewish women expended 2250 kcal (9420 kj) per day in the summer and 2 390 kcal (10 000 kj) per day in the winter. Integrated heart rates were recorded in the two seasons, during the night and during the day. The night rates were significantly lower in the summer than in the winter. The average night rates were: summer, winter, beats/min beats/min Kurdish Jews men 56.3 60.9 women 63.0 70.6 Yemenite Jews men 60.4 65.6 women 66.6 70.5 The time spent out of doors in the daylight hours was 348 min/day in the summer and 347 min/day in the winter for the Yemenite Jewish men. The Kurdish Jewish men spent 401 min/day out of doors in the summer and 342 min/day out of doors in the winter. The Yemenite Jewish women were out of doors for 205 min/day in the summer and 243 min/day in the winter. The corresponding figures for the Kurdish Jewish women were 203 and 81 min/day.

The diurnal change in temperature and height measured by the new U.S. Weather Bureau outrigger radiosonde at and above 100 mb. has been determined from pairs of successive radiosonde observations taking place in daylight and darkness. Analyzed graphs of the change as a function of solar elevation angle are presented. For a given solar angle, the observed diurnal variations are found to be larger with afternoon daylight than with morning daylight. Furthermore, values computed for Plateau stations with afternoon daylight are particularly large. Use of the white 50-mil rod thermistor with outrigger mounting has radically improved the compatibility of reported temperatures and heights at adjacent stations, primarily because the radiational temperature error has been reduced by a factor of about two to four. The observed diurnal variations measured by this new instrument are comparable with those of the military outrigger radiosonde, allowing for the slightly smaller thermistor of the latter.

In the year 1864 I communicated to the Royal Society the description of a method for the Meteorological Registration of the Chemical Intensity of Total Daylight, founded upon an exact measurement of the tint which standard sensitive paper assumes when exposed for a given time to the action of daylight. During the last two years measurements of the chemical intensity, according to this plan, have, through the kindness of Dr. Balfour Stewart, been made regularly every day at the Kew Observatory by Mr. T. W. Baker, and thus the practicability of carrying at a continued series of observations according to this method has been effectually and satisfactorily tested.

Simple equations are obtained for ascertaining the window area necessary to secure a given penetration of daylight into a room and for the determination of daylight contours. Evidence is given to s...

Bissonnette's (1932) remarkable discovery that additional illumination would induce œstrus in anœstrous ferrets has naturally led to much speculation as to what controls the onset of the breeding season in the normal ferret. An obvious interpretation of Bissonnette's results, and one apparently favoured by Marshall (1932), suggested that the beginning of the breeding season of the normal female in March-April is influenced by the increasing duration of daylight. Such a hypothesis, however, could not be extended to many mammals. Those breeding in the autumn (sheep, for instance) would require a radical alteration of the hypothesis, while nocturnal and subterranean mammals can hardly be affected directly by the duration of daylight. Even in the ferret the hypothesis scarcely seemed valid, because the initial breeding season changes are evident histologically in December and January (Allanson, 1932). The converse experiment, keeping breeding season animals in daylight of winter duration, was also attempted by Bissonnette (1933), but the results were inconclusive. A somewhat similar experiment was therefore carried out in London, under the very stringent conditions of keeping the animals in total darkness except at the time of feeding. The results offer little support to the theory that length of daylight has any controlling influence on normal sexual periodicity.

A cause of erroneous temperatures obtained in the earlier phases of a study using standard radiosondes flown on constant-level balloons at White Sands Missile Range is discussed. A simple and inexpensive modification of the radiosondes which produces more accurate ambient temperatures on daylight flights is described.

During IGY the American Radio Relay League collected radio amateur reports of 50- and 144-Mc/s ionospheric propagation, evaluated them, and transcribed them onto punched cards. Analysis of 50-Mc/s equatorial intercepts, begun this summer at Stanford University, has revealed three apparently related types of nocturnal, low-latitude propagation: (1) long-range transequatorial, as first noticed by amateurs in 1947; (2) medium-range, between stations making transequatorial contacts and stations near the magnetic equator; (3) short-range, similar to sporadic E but occurring regularly with the first two types. Where ever they appear these modes are present almost nightly during certain months, and evening propagation of frequencies up to 1.5 times the maximum daylight MUF is not uncommon. Comparison of transequatorial results in the Americas and the Far East has shown that seasonal behavior is not the same at all meridians. Pronounced negative correlation with magnetic activity is a world-wide feature, however, which suggests a direct relation to equatorial spread F. Quantitative professional data at the frequencies of interest are rather rare, but comparisons with Professor Dueno's backscatter soundings made at the University of Puerto Rico indicate that the 20- and 40-Mc/s transequatorial propagation seen there is not the same as what amateurs experience on 50 to 75 Mc/s.

A method is described by which direct daylight factors can be obtained directly from photographs, or from images projected on a ground-glass screen, by means of suitable grilles. These may also be used for the prediction of direct daylight factors.

The colours of total radiators are discussed and methods of estimating the colour-temperature to be assigned to a colour not on the locus of the colours of total radiators are outlined. The filter method of calibrating tungsten lamps at the National Physical Laboratory is given, with an indication of the probable accuracy of the calibration. The history and properties are given for the three standard illuminants A, B and C recommended for colorimetry by the Commission Internationale de l'Eclairage in 1931. Other illuminants, such as the equal-energy illuminant E, are mentioned, and the colours of them are compared with those of daylight.

The in vitro nematicidal activity of α-terthienyl was markedly enhanced when at the same time radiation with daylight or specific parts of the daylight spectrum was applied. Near ultra-violet light appeared to be the active part of the daylight spectrum. The same effects were found with two synthetically prepared nematicidal dithienylethenes and 2,3-dihydro-2-hydroxy-3-methylene-6-methylbenzofuran, a natural nematicide from roots of a Helenium hybrid. A common feature of these compounds is their absorption in the near ultra-violet region. Nematodes released α-terthienyl but more slowly than it was taken up.

Rainbow trout in artificial stream situations were offered seven colors of dyed rainbow trout eggs in all combinations of two colors. Against a pale, greenish-blue background, in daylight, the color preference was: blue, red, black, orange, brown, yellow, and green. This order largely reflected contrast with background color; but, in addition, there were preferences for certain colors. Particular color combinations such as yellow and black, and yellow and blue, resulted in significantly higher total consumption. When background color was varied, preference was low for the color of eggs that matched the background, but the effect was not statistically demonstrable. At low light intensities the order of preference for various colors was yellow, red, blue, and black. The results collectively indicate keen color discrimination in rainbow trout and preferences for particular colors in particular environmental settings. These findings could have useful application to field situations where it is desirable to modify rates of predation on salmon fry by presenting other kinds of food to satiate predators.

Extensive field studies in the Colorado headwaters area, largely in Grand County, Colorado, disclosed that, although average plant distribution was in general accord with that in previously published reports and closely approximated that in environmentally similar areas elsewhere, the altitudinal ranges of various species varied markedly from valley to valley. Even when due corrections were made for gross climatic conditions, effective daylight, available soil moisture, and soil chemistry, a large part of this variation remained to be accounted for. Microclimatic investigations in a number of valleys in this area (Ives, '38, '41, '42) showed that strong diurnal air circulations were common. to all of them. In large part, altitudinal deviations from average in the ranges of various species were in the direction indicated by the biotic effect of the locally dominant air drift. Consideration of the data accumulated during study of more than 100 valleys in the Rocky Mountain region, augmented by less intensive studies in mountain areas elsewhere in North America, indicates that characteristic altitudinal patterns accompany three general types of valley air circulation. These are

SummaryAs part of a general study of the conditions required for satisfactory maintainance ofPieris brassicae(L.) in laboratory culture, an investigation was made of the factors affecting mating behaviour. Notes are given on certain characteristics of the culture from which the experimental material was drawn.It was established thatP. brassicae, over one day old, mated readily at temperatures between 20 and 32°C. provided the daylight illumination was above about 200 lumens/sq. ft. Mating occurred more readily at the higher temperatures and illumination levels than at the lower. It was depressed at very high atmospheric humidities. The size of the cage in which the insects were held was not critical, and pairs formed readily in cages as small as one cubic foot. The population density in the cage was also varied over wide limits without significantly influencing the rate at which pairs formed.Mating took place much less readily in the artificial lights which were tested than in daylight. The most satisfactory light was found to be bilaterally arranged ‘daylight ’-type fluorescent lamps. The level of mating in this light would probably have been sufficient to maintain a culture but it was far lower than in daylight of the same intensity.After mating, the females do not usually pair again for five or more days. The males, however, mate more frequently and will often pair several times in the same day.

本論文は美術品陳列室の明り天井に依る書光照明に就て述べてある. 測定は實際の寸法の模型竝に實際の美術館に就て行つた. 明り天井に依る畫光照明に最も適當な明り天井と床面積との比並に不均一度を與へてある.

This report to the International Research Council on solar and radio relationships shows that the relationships are closer at short wavelengths than at long, that the effect of magnetic storms, which are assumed to be due to solar action, is, in general, to weaken night signals at all wavelengths and in the medium and long-wave ranges to strengthen day signals. Curves are given which show that there is a direct correlation between the yearly averages of long waves, daylight transatlantic signals, sun spot numbers, and magnetic activity (1915-1930), a direct correlation between signals and magnetic activity averages by months (1924-1930), and an inverse correlation between sun spots and atmospheric disturbances averages by years (1918-1930).

The instrument consists of a solarimeter fitted with a hemisphere of heat-absorbing glass. By this means, a well-tried instrument, already widely used in meteorological stations for the measurement of total incident radiation, is converted into an instrument suitable for measuring photosynthetically active radiation. The good angular response is preserved by using a hemispherical filter. With a commercial electronic microvoltmeter the instrument is sensitive enough for use in phytotrons, and if photosynthetically active radiation is assumed to be bounded by the wavelengths 0.4 and 0.7μ, calculations show that it compares irradiances of common light sources with daylight, in these units, with an error of not more than 20%, reducible to 10% with an improved filter glass. Arguments are presented for specifying and measuring light directly in such units, here called “plantwatts/m 2 ”, rather than using illumination units and a conversion factor for each light source. Daylight measurements with a filtered and an unfiltered solarimeter over several months have shown that the number of plantwatts/m 2 is not a constant proportion of the total irradiance but varies (in one locality) from 48 to 65%. Moreover, the variation is systematic, the highest proportions occurring during the dullest weather, presumably because water vapour is the chief absorber involved. A systematic error would, therefore, be introduced by measuring with an unfiltered solarimeter and assuming that the proportion of photosynthetically active radiation in daylight is constant.

A method is developed and described for forecasting whether measurable precipitation will occur at Washington, D. C., during the daylight hours “tomorrow” using meteorological information which is available to the forecaster during the early morning hours “today,” namely the upper air observations taken “yesterday.” Methods which the author had previously developed for use during summer and winter months were found ineffective when applied to October data. In the present system the initial assumption is made that rain will occur during the specified period. Procedures are then applied for eliminating rain from the forecast. Unless a rule is found which states that rain will not occur, rain is forecast. Results obtained when the system is applied to Baltimore, Md., and Richmond, Va., using the same variables as used for Washington, D. C., are also shown.

This is an account of the commercial production of Trichogramma during the season of 1930. Improved types of equipment are described. Parasitism by Trichogramma was obtained in complete darkness as well as in daylight.

Even in daylight in clear conditions the driver's visibility, both forward and rearwurd, is restricted by the structure of the vehicle. Important sections of the view can be obscured ; thus a windscreen pillar can obscure a pedestrian Or cyclist until it is too late to avoid an accident. A given vehicle has certain visibility characteristics. The work described in this paper is the measurement of these characteristics for a range of vehicles. The method of measurement is based on an American technique in which two lamps are positioned to correspond with the eyes of an average driver. The visibility is measured by moans of the shadows cast by body pillars, bonnet, etc., and by the light reflected rearwards by the mirror. Both forward and rearward visible areas can be interpreted as plans of visible areas on the ground, In the choice of eye position, consideration was given to the position of the eyes relative to the teat and to the position of the seat in its travel, The seat is positioned with reference t...

This paper outlines the theory behind the development of a set of tables for the field reduction of azimuth observations on elongating daylight stars. The merits of the method, namely that the results are independent of latitude and that the calculations are very much simplified, are brought out. The use of the tables is discussed and samples are presented.

During the winter months of 1963 and 1964, mature non–pregnant Clun Forest ewes at pasture were equipped with pedometers to study the value of these instruments for measuring distances walked, and to investigate the importance of weather on the distances travelled. Approximately 80 periods were recorded, each of about 24 hours. The accuracy of the measurements was checked by using a rangemeter and it was found that the reliabihty of pedometer records must be assessed on the animal from which they are obtained. The individual characteristics of the pedometers and/or the sheep gave rise to inaccurate records from about 50% of the instruments studied. Multiple regression analysis of data for each of the three sheep which provided suitable records revealed that, in dry weather, the average distance walked per hour of recording period increased signiJBcantly with mean air temperature in one case and with hours of bright sunshine in another. Wind–speed effects were unimportant. The distance walked by all three sheep increased significantly with hours of daylight per recording period, and this was the only variable found to affect distance walked in wet weather. Differences between average distances walked per hour under dry–and wet–conditions were non–significant. It is concluded that for measuring the distances walked by sheep, the disadvantages of the pedometer outweigh its advantages.

Among birds it is generally believed that both the male and the female share the duty of incubation alternately. The reason why they do this is not yet well explained. The author experimented on this problem, and although it is by no means complete, revealed the following fact. Under the natural daylight and darkness the female incubates in a given box between about 4 p. m. and 10 a. m. the following morning, and the male during the remaining daylight hours. When the nest box is curtained and shuts out natural light to a certain extent the changing time becomes late in the morning and becomes early in the afternoon. The male, when the daylight is longer appears to be willing to sit longer.