I.—An Experimental Investigation of the Temperature Changes occurring in Fresh-Water Lochs.

1908 ◽  
Vol 28 ◽  
pp. 2-20 ◽  
Author(s):  
E. M. Wedderburn
Keyword(s):  
Experimental Investigation ◽  
Fresh Water ◽  
Laboratory Experiments ◽  
Present Communication ◽  
Temperature Changes ◽  
Previous Communication ◽  
Temperature Observations ◽  
Made In

In a previous communication published in the Transactions of the Society (vol. xlv., part ii., p. 407) I attempted to discuss the temperature observations made in Loch Ness during the years 1903 and 1904. Some of the conclusions which I arrived at have not been generally accepted, and in particular limnologists have been slow to acknowledge the existence of the temperature seiche first described by Mr Watson, and which I consider was fully borne out by the observations published in my previous communication. In order to get some ocular demonstration of the possibility of such a phenomenon, I had recourse to laboratory experiments, and it is the description of these experiments which is the main object of the present communication. Besides demonstrating the nature of the temperature seiche, the experiments also throw light on the formation of what has been called by German and Austrian writers the Sprungschicht, and which I now propose to call in English the ‘discontinuity layer,’ which, with the word Sprungschicht, has the merit of being descriptive.

scholarly journals XXVI.—Temperature Observations in Loch Earn. With a further Contribution to the Hydrodynamical Theory of the Temperature Seiche

1913 ◽  
Vol 48 (3) ◽  
pp. 629-695 ◽  
Author(s):  
E. M. Wedderburn
Keyword(s):  
Fresh Water ◽  
Meteorological Conditions ◽  
The Body ◽  
Detailed Knowledge ◽  
Temperature Changes ◽  
Accurate Knowledge ◽  
Temperature Observations ◽  
Considerable Depth ◽  
Hydrodynamical Theory

There are a number of gaps which exist in our knowledge of the temperature changes which occur in fresh-water lakes. The broad lines on which the changes occur are fairly well known, but on almost every point there is a lack of detailed knowledge, and every investigation shows new problems requiring attack. One of the most interesting of these problems is the causation of the temperature seiche, and the effect of varying meteorological conditions. The problem is a difficult one, as the factors to be taken into consideration are so numerous, and the data from which to form conclusions are difficult to procure. We must first obtain an accurate knowledge of the changes which are occurring in the body of water under consideration—not only at one point but at all points, and this necessitates observations at frequent intervals of time, at numerous depths, made from several points on the surface of the loch. As yet there are no satisfactory self-recording instruments by means of which we can record the temperature of water at a considerable depth below the surface, and recourse must be had to the reading of mercury thermometers.

XXXVIII.—Observations with a Current Meter in Loch Ness

1909 ◽  
Vol 29 ◽  
pp. 619-647 ◽  
Author(s):  
E. M. Wedderburn ◽  
W. Watson
Keyword(s):  
Experimental Investigation ◽  
Fixed Point ◽  
Great Lakes ◽  
Large Lake ◽  
Deep Lakes ◽  
Small Lake ◽  
Stormy Weather ◽  
Set Up ◽  
A Current ◽  
Made In

One of the authors having made an experimental investigation on the currents produced in a trough of water by a blast of air driven along the surface of the water, it was desired to test the correctness of his deductions by actual observations in a large lake. Loch Ness was chosen on account of its length and uniformity of basin, as it was thought that the length and narrowness of the loch would lead to clearly defined currents being set up in the lake. The sequel showed, as in the case of observations on seiches, that it would have been better to confine attention to a smaller lake, for a twofold reason, (1) because in a large lake the difficulties of observations are much greater than in a small lake during stormy weather, and in very deep lakes the difficulties in the way of obtaining a fixed point from which to use the current meter are formidable, and (2) because it would seem from a few observations made in Loch Garry (Ness Basin) that currents are more defined and more regular in small than in great lakes.

An experimental investigation of current production by means of rotating magnetic fields

1981 ◽  
Vol 26 (3) ◽  
pp. 465-480 ◽  
Author(s):  
W. N. Hugrass ◽  
I. R. Jones ◽  
M. G. R. Phillips
Keyword(s):  
Magnetic Field ◽  
Experimental Investigation ◽  
Threshold Value ◽  
Rotating Magnetic Field ◽  
Electron Current ◽  
Rotating Magnetic Fields ◽  
Theta Pinch ◽  
Current Production ◽  
Made In ◽  
Rotating Field

An investigation of current production by means of a rotating magnetic field is made in an experiment in which the technique is used to generate a theta-pinch- like distribution of field and plasma. Detailed measurements are made of both the generated unidirectional azimuthal electron current and the penetration of the rotating field into the plasma. The experimental results support the theoretical prediction that a threshold value of the amplitude of the applied rotating field exists for setting the electrons into rotation.

Evaluation of acute toxicity of zinc, lead and cadmium to zooplanktonic community in upper Berach river system, Rajasthan, India

2012 ◽  
Vol 2 (1) ◽  
pp. 20-26
Author(s):  
Nadim Chishty ◽  
Anil Tripathi ◽  
Madhusudan Sharma
Keyword(s):  
Heavy Metal ◽  
Acute Toxicity ◽  
Fresh Water ◽  
River Basin ◽  
Laboratory Experiments ◽  
River System ◽  
Daphnia Lumholtzi ◽  
Lead And Cadmium ◽  
Sensitivity Pattern ◽  
Static Bioassay

Current study investigated through static bioassay, the acute toxicity of Zinc,Lead and Cadmium to fresh water zooplankters in the upper Berach riversystem which is a part of Gangetic river system. The river basin stretchesfrom Madar tank to Sarjana tank with a total length of 46 Km, including ninewater bodies i.e. Bada madar tank (73‹36f0ffE and 24‹38f0hN ), Chhotamadar tank, Fateh sagar lake, Udaisagar lake, Up]stream pond (Bichhdi]I),Down]stream pond(Bichhdi]II), Gadwa, Daroli and Sarjana tank (73‹ 57f10hEand 24‹14f30h N). Whole zooplanktonic communities were exposed to different heavy metal stresses. Exposed zooplanktonic community included nine planktonic forms i.e. Heliodiaptomus viduus, Mesocyclops hyalinus, Heterocypris, Daphnia lumholtzi, Moina, Brachionus, Monostyla, Filinia. Cadmium was found to be most toxic and Zinc was least toxic to zooplankton. Ostracods and Cyclops were resistant forms and rotifers were sensitive forms in relation to metallic exposure. Sensitivity pattern observed during laboratory experiments was found to be in accordance with biodiversity variation of zooplankton in different ponds of Berach river system.

scholarly journals XIX. On the photographic arc spectrum of iron meteorites

1894 ◽  
Vol 185 ◽  
pp. 1023-1028
Keyword(s):  
Royal Society ◽  
Solar Spectrum ◽  
British Museum ◽  
Iron Meteorites ◽  
Electrolytic Iron ◽  
Comparison Spectrum ◽  
Size And Shape ◽  
Previous Communication ◽  
Oxyhydrogen Flame ◽  
Made In

In a communication to the Royal Society in 1887, I gave an account of certain experiments which I had made in connection with the spectra of various meteorites at various temperatures. The spectra were observed at the temperature of the oxyhydrogen flame and the electric spark without jar, and when glowed in vacuum tubes. Some larger specimens of the iron meteorites, Nejed and Obernkirchen, cut so that they were of a size and shape suitable for forming the poles of an arc lamp, having afterwards been kindly placed at my disposal by the Trustees of the British Museum, it became possible to study the arc spectra of these meteorites under very favourable conditions, all impurities introduced by the use of the carbon poles being thus avoided. The region of the spectrum photographed extends from K to D, in the case of each meteorite, and in addition to the solar spectrum, that of electrolytic iron, prepared by Professor Roberts-Austen, referred to in a previous communication, has been used as a comparison spectrum in one case.

scholarly journals Some Fresh Water Algae of Eastern Uttar Pradesh, India

Our Nature ◽  
1970 ◽  
Vol 3 (1) ◽  
pp. 77-80 ◽  
Author(s):  
P.K. Misra ◽  
A.K. Srivastava ◽  
J. Prakash ◽  
D.K. Asthana ◽  
S.K. Rai
Keyword(s):  
Key Words ◽  
Fresh Water ◽  
Uttar Pradesh ◽  
Present Communication ◽  
Taxonomic Description ◽  
Eastern Uttar Pradesh

Present communication deals morpho-taxonomic description of 11 fresh water algae belonging to class Chlorophyceae and Bacillariophyceae. Chlorophycean genera are Pediastrum Meyen (1 sp), Cladophora (2 spp), Staurastrum (3 spp), Onychonema (2 spp) and Desmidium (1 sp) while Bacillariophycean genera are Navicula (1 sp) and Rhopalodia (1 sp). Key words: Bacillariophyceae, Chlorophyceae, Eastern Uttar Pradesh, Fresh water algaedoi:10.3126/on.v3i1.338Our Nature (2005) 3: 77-80

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