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Subjects' perceptions of cues used to judge intoxication across different drinking settings were investigated. College students (N = 40) were presented with 12 one-paragraph scenarios, four for each of three types of drinking expectancy: tension reduction, social disinhibition and physical impairment. Pilot testing confirmed that the scenarios accurately represented these different expectancies. Subjects rated the importance of 18 cues to intoxication for judging intoxication in each of the 12 scenarios. Results indicated that 15 of the 18 cues were perceived to be differentially important in the three types of situations. These results suggest that subjects apply cues to intoxication differently in different situations.

The identification of the magnetic dipole rotation spectrum of oxygen in atmospheric studies has been confirmed by laboratory measurements in the spectral range 12 to 65 cm -1 , using interferometric techniques combined with long absorption paths and pressures of 2 to 3 atmospheres. A quantitative comparison has also been made between the laboratory observations and the theoretical predictions, giving agreement in the frequencies to within +0∙026 cm -1 and that of the integrated line-strengths within experimental error, as defined by the signal/noise ratio of the observed spectra.

A study of water vapour absorption at two submillimetre wavelengths (337 μm and 311 μm) has been made as a function of foreign gas pressure using A, CH 4 , N 2 and CO 2 as the broadeners in order to explain excessive absorption in the atmospheric “window” regions. As an extension of this work the absorption coefficient of water vapour alone was measured as a function of pressure and temperature. From an analysis of the ratio of the absorption coefficients at the two wavelengths, the anomalous absorption has been explained in terms of three contributions. 1. 1. A background absorption which is independent of foreign gas broadening. This is ascribed to two-body collisions in water vapour which may be explained in terms of a dimeric form of the water molecule having a binding energy of (5·2±1·5) kcal mol -1 . 2. 2. A modification of the line shape in the far wings which is dependent upon the foreign gas pressure and quadrupole moment. This effect is consistent with a two body quadropole collision-induced background absorption. 3. 3. A three-body effect which is related to the quadropole moment of the foreign gas used to broaden the water vapour lines.

In an attempt to find the cause of an unexpected absorption feature that exists near 8 cm -1 in the millimetre-wave spectrum of the Earth's atmosphere, we have performed laboratory experiments using Fourier Transform spectroscopy, the results of which are presented in this paper. We have duplicated atmospheric conditions as closely as possible and have examined the absorption spectrum of cold water vapour in the wave-number region 5 to 30 cm -1 . The new feature was observed in the laboratory and its integrated absorption strength, S , has been measured as a function of both pressure and temperature. S varies as the square of water vapour density, indicating a dimeric effect: in addition we have obtained a value for the association energy, Δ E , of the dimer from the temperature variation of S , and find Δ E = 6±3 kcal mol -1 , in agreement with the predicted value of 5 kcal mol -1 for the hydrogen bond energy between two water molecules. Together with these results we present a short discussion of the possible implications that the observation of this new absorbing species may have in sub-millimetre atmospheric physics.

Observations have been made of the submillimetre wavelength radiation emitted by the lower stratosphere, using techniques of Fourier transform spectroscopy, while flying in a Comet 2E aircraft. Using the method of phase-modulation high quality spectra have been obtained at several altitudes over the spectral range 20 to 66 cm−1, and these have enabled identification of many emission lines due to O2 and O3, in addition to those of H2O. Also several unidentified emission lines have been observed. The meteorological applications of this spectroscopic technique are considered. In particular, a direct method of comparing the emission of ‘strong’ water-vapour and oxygen lines enables a calculation of mixing ratio of water vapour in the stratosphere to be made, and a value of (2.1 ± 0.3) × 10−6 g/g is derived above an altitude of 12.2 km. A similar comparison for ozone has given an integrated concentration of 0.35 ± 0.10 cm atm in the vertical path above the observer. The merits of these observations in measuring stratospheric mixing ratios are discussed with respect to alternative techniques, in particular with reference to balloon-borne studies.

Molecular coincidences with the 337 mu m HCN maser line have been identified by the techniques of pressure-broadening spectroscopy and intracavity absorption. A study has been made of the variation of the absorption coefficients of acetone ((CH3)2CO), propionitrile (C2H5CN) fully deuterated acetonitrile (CD3CN) and 1,1,-difluoroethylene (CF2=CH2) at 337 mu m wavelength, and of the absorption coefficient of CD3CN at 311 mu m wavelength. From these measurements the positions of the nearest pure rotation lines relative to the 337 mu m emission have been inferred. These measurements have been used to predict the way in which the maser output would be modified by intracavity absorption, and these predictions have been confirmed experimentally. A discrete absorption feature has been obtained in the case of CF2=CH2. This feature is estimated to be of the order of 2 MHz on the low-frequency side of the centre of the maser emission at 890 GHz (337 mu m). Possible applications of this result are discussed briefly.

WE have discussed the possibility that HNO3 is responsible for several unassigned lines in the submillimetre emission spectrum of the stratosphere1–3. This possibility was suggested by the observation of this molecule in the stratosphere in mid-infrared studies by Murcray et al.4,5 and a consideration of the large dipole moment (intense lines) and the large moments of inertia (allowing a pure rotation spectrum at long wavelengths) led us to believe that this species might just be observable at submillimetre wavelengths.

As a result of a number of high altitude submillimetre atmospheric observations using both the Sun1–4 and the sky5,6 as a source, there is interest concerning the origin of a number of weak absorption features that have appeared in these spectra. In particular a result obtained at an altitude of 12.6 km (ref. 4) has given tentative assignments to a number of the features observed. We present here laboratory results aimed at explaining certain features in the region 19 to 31 cm−1 in terms of isotopic modifications of water vapour (HDO and H2O18) (ref. 7) and the rotational transitions of the lowest vibrationally excited state of H2O16 (v1, v2, v3 = 0, 1, 0, centred at 1,595 cm−1 (ref. 8) Transitions resulting from these species apparently have not been considered in analysing atmospheric results. Also we present a result which has been referred to in both refs. 2 and 4, namely, an atmospheric absorption spectrum in the region 40–54 cm−1, again with the purpose of identifying any weak features attributable to both isotopic species of water vapour, and the dimer of the water molecule2,3,9.

Two experiments using an interferometer and a maser have indicated the occurrence of submillimetre wave absorption by dimeric water. This form of water seems to exist in the Earth's atmosphere.

A SUB-MILLIMETRE wave observation1 of the Sun, obtained in December 1967 at an altitude of 3,580 m, indicated an unexpected absorption feature in the range 7–9 cm−1, and thus confirmed an earlier unpublished result obtained as part of a study in March 1957 at the same site2. Because of the long atmospheric path during the more recent experiment, the spectral quality in the 20–30 cm−1 range was modest. In order to obtain better solar results over this range, further observations were made in April 1968 when the air mass in the observation path was smaller and comparable with that of March 1957.

The present research investigates the hypothesis that cognitive representations of large scale space contain elements that may be termed reference points, and that these points are used to define the position of adjacent places. The nature and function of reference points is explored in five experiments. Experiments 1 and 2 consist of tasks during which subjects judged the distance between known locations. The subjective distance between reference points and nonreference points was found to be asymmetrical, with the latter ordered in relation to the former. Experiments 3 and 4 employ reaction time tasks in which subjects attempted to verify the distance or direction from an anchor location to target locations. The data indicate that the relative referentiality of anchor and target locations influences verification time. The results of Experiments 1-4 suggest that reference points occur in spatial cognition and that these points provide an organizational structure that facilitates the location of adjacent points in space. Experiment 5 consists of a multiple regression analysis designed to clarify the semantic attributes of spatial reference points.

The submillimeter-wave properties of the atmosphere are determined largely by the spectrum of water vapour. Although oxygen and ozone, for example, have significant features, it is the pure rotation spectrum of monomeric water vapour that dominates all else. As a consequence, solar radiation is detectable at sea level only beyond about 1000 μm and at 3000 m altitude it is detectable above 280 μm with the bulk of the detected power lying in two windows centred at 357 and 454 μm (Gebbie, 1957).

THE measurement of the mixing ratio, μ, of water vapour to air in the stratosphere has been carried out many times, using spectroscopic methods, from both aircraft1,2 and balloons3–6. As a result of the range of values that have been obtained the subject has become controversial6,7. We present here some submillimetre wavelength measurements made in an aircraft observing atmospheric emission, using methods of Fourier transform spectrometry8, which may provide an improved method of obtaining this parameter. Previous sub-millimetre atmospheric emission measurements9 have produced estimates of stratospheric water content, but the quantitative value of these results is limited because of the problem of radiometrically calibrating the system in order to obtain reliable measures of background and zero levels. In the present work the direct comparison of water vapour and oxygen emission has largely removed these requirements and greatly simplified the analysis.

The possibility of dimers of the water molecule, for which there was considerable evidence on the basis of P-V-T virial coefficient measurements (Rowlinson, 1945), having a significant atmospheric absorption was first proposed theoretically by Viktorova and Zhevakin (1967). They calculated the submillimetre and millimetre spectrum on the basis of a linear or open structure model (Pauling, 1960) of the dimer in order to provide an adequate explanation for the well known excessive absorption observed in atmospheric ‘windows’ in this region (Dryazin et al., 1966; Ryadov et al. 1966; Burroughs et al., 1966). This theoretical work also predicted the existence of a discrete absorption feature in the spectrum at 7.1 cm-1, which being in a ‘window’ region should be observable in atmospheric studies. At about the same time broad-band observations of the Sun in the millimetre range indicated a feature in the range 7 to 9 cm-1 (Gebbie and Burroughs, 1968), which appeared to be correlated with water content. In order to determine whether these effects are indeed due to the dimer of water vapour a number of submillimetre wavelength experiments have been carried out, both in the laboratory, and in the field observing solar radiation attenuated by the atmosphere. The results considered will consist of: (a) spectroscopic studies of the 7.5 cm-1 feature showing the necessity to work at low temperatures and low total pressure in order to observe this line, and (b) monochromatic maser absorption measurements showing that the excess absorption in the ‘window’ regions can be observed at high temperatures and high total pressures. These apparently contradictory properties of the dimer absorption will be shown to be both of interest in making improved measurements of the parameters of this molecule, and also of importance in estimating its effect on the properties of the atmosphere.

PRELIMINARY work1 gave a spectrum covering the wavelength range 1 mm to 300µ. of solar radiation passing through the atmosphere under conditions of low total water vapour. The expected absorption features resulting from the pure rotation lines of water vapour were recorded, but additional absorption features were present which could not be attributed to water and which in the earlier account1 were tentatively ascribed to ozone, as this is the only other major atmospheric constituent with a permanent electric dipole moment. Subsequent experimental observations on ozone in the laboratory together with the analysis of E. K. Gora2,3 showed that this explanation was not correct. About 3 years ago it was suggested that the absorption features at 14.2, 16.2 and 27.8 cm−1 (Fig. 1) could be attributed to molecular oxygen which has a permanent magnetic dipole moment. Transitions had been predicted which provided a plausible explanation of the observed features, but no observations of the magnetic dipole rotation spectrum had been reported. The present work was undertaken to check at least qualitatively that this absorption was as predicted; this communication reports our preliminary results.

From this value, which is considerably greater than the value predicted from known strengths and line shapes of water lines, an estimate of the variation of atmospheric transmission with altitude can be made after correction for pressure and temperature. At 3500 m with 2 mm of precipitable water in the observation path a transmission of the order of 5 % can be expected in the centre of the 27—30 cm-1 window. Hence, solar observations such as centre to limb measurements and blackbody temperature estimates in this window are quite feasible at this altitude. The unidentified features in the solar spectrum (Gebbie 1957) have now been identified as due to the pure rotation magnetic dipole spectrum of molecular oxygen (Gebbie, Burroughs, Robb & Bird 1966), a result which has been confirmed by long-path laboratory measurements. Recently, observations have been made from an aircraft flying at 12 000 m (Bader, Cameron, Burroughs & Gebbie 1967) and it was shown that by measuring the exchange of radiation’between a hot detector and the cold sky, the transmission of the upper atmosphere could be measured. This work showed that at this altitude the atmosphere was relatively transparent in the regions 42-46 and 48-52 cm-1 and that these regions give possible extensions to the wave-number range of astronomical observation.

WE present here the results of experiments started in 1957, to which have been added some observations made in December 1967 using a new telescope at Hochalpine Forschungssation Jungfraujoch (altitude 3,580 m).

WE wish to report the results of experiments aimed at verifying the prediction that sub-millimetre waves would be scattered relatively little by fog. The availability of a stimulated emission source of radiation of wavelength 0.337 mm1, at which frequency the atmosphere is relatively transparent (Fig. 1), has made measurements possible, but the number of observations has been severely limited by the rarity of dense natural fogs on the sites available to us.

A PRELIMINARY experiment has been carried out to investigate the feasibility of making submillimetre wave measurements from a jet aircraft flying in the stratosphere. The value of such aircraft as observation platforms is that very low values of water vapour content in the line of sight can be obtained and water vapour is the dominant atmospheric absorber at submillimetre wavelengths. In this sense the experiments can be regarded to continue those made at high altitude observatories1,2, but to improve on them greatly because it was possible to determine lower total water values.

Transmission spectrum of upper atmosphere measured from aircraft at 39,000 ft, noting atmospheric oxygen and ozone absorption lines