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Removal Of A Common Source Of Trouble In Hydrogen Ion Measurements, Stephen Popoff, A. H. Kunz
Removal Of A Common Source Of Trouble In Hydrogen Ion Measurements, Stephen Popoff, A. H. Kunz
Proceedings of the Iowa Academy of Science
The best conditions for plating platinum black deposits are given. If these conditions are followed, it is rather difficult to "poison" the hydrogen electrodes in the ordinary neutralization reactions. Poisoned electrodes can be restored to give normal values if treated with concentrated nitric acid.
Temperature Studies Of Lake Okoboji For 1925, Frank A. Stromsten
Temperature Studies Of Lake Okoboji For 1925, Frank A. Stromsten
Proceedings of the Iowa Academy of Science
Continuing the work begun by Tilton ('15-'16) and Birge and Juday ('19), the writer has, since 1922, made daily observations of the water temperatures of Lake Okoboji. Sample readings have been reported from time to time. Temperature curves for the several years under observation show considerable variation in the degree of zonation. Tilton's curves do not show any marked differentiation into epilimnion, thermocline, and hypolimnion. On the other hand in 1919 Birge and Juday's observations show a very distinct zonation. This is even more marked in the curves for 1922 (Stromsten '23) and reaches its climax in 1923 (fig. 1). …
A Case Of Abnormal Development In Gallus Domesticus With Notes On Similar Cases In Other Species, F. L. Fitzpatrick
A Case Of Abnormal Development In Gallus Domesticus With Notes On Similar Cases In Other Species, F. L. Fitzpatrick
Proceedings of the Iowa Academy of Science
The production of "developmental monstrosities" in the species Gallus domesticus has been observed in a number of cases. It is safe to say that few of these "monstrosities" have been subjected to more than a passing investigation or have been recorded in the literature. Perhaps the recording of more complete data on this subject would show that such occurrences are not uncommon. Whether such investigation or the discovery of the cause of such abnormal development would have any part in solving some of the problems of heritage and development is an open question.
A Modern Cataclysm, Harry M. Kelly
A Modern Cataclysm, Harry M. Kelly
Proceedings of the Iowa Academy of Science
Wholesale but selective destruction of clams, by a cyclonic storm, occurred last summer along the western and northwestern shores of Spirit Lake, Iowa, where shallow water, soft bottom, gentle slope and abundance of clams were correlated with an unusually heavy and long continued on-shore wind.
Some Investigation Of The Ethanol Carbontetrachloride System, S. Fred Calhoun, Thos. C. Poulter
Some Investigation Of The Ethanol Carbontetrachloride System, S. Fred Calhoun, Thos. C. Poulter
Proceedings of the Iowa Academy of Science
The Ethanol Carbontetrachloride system has been investigated with respect to the total vapor pressure, and the partial vapor pressures of the constituents at twenty-five and sixty degrees. The total pressures of different mixtures of Ethanol Carbontetrachloride were determined at twenty-five degrees by means of a bulb to which was sealed a manometer. The total pressure at sixty degrees was measured by means of an apparatus designed by the authors for the rapid and accurate determination of the vapor pressures of liquids that do not readily react with mercury. A description of this apparatus will appear in the Journal of Industrial …
A Reconsideration Of The Age Of Certain Outliers In Linn And Jackson Counties, W. H. Norton
A Reconsideration Of The Age Of Certain Outliers In Linn And Jackson Counties, W. H. Norton
Proceedings of the Iowa Academy of Science
At Bertram in Linn county and at Canton in Jackson county are found deposits of sandstone, shale and clay, called by courtesy outliers, though very limited in area and thickness, which carry Devonian fossils. Their importance lies in the fact that if their assignment to the Devonian by the writer in 1893 is correct, they imply a significant transgression of the Devonian sea over east central Iowa.
The Solar Surface During The Past Five Years A Review Of Sunspot Observations Made At Alta Iowa From 1921 To 1925, David E. Hadden
The Solar Surface During The Past Five Years A Review Of Sunspot Observations Made At Alta Iowa From 1921 To 1925, David E. Hadden
Proceedings of the Iowa Academy of Science
Observations of the solar surface were commenced by the writer in August, 1890, and brief reviews have been published in these Proceedings from time to time, the first being in Volume X, 1902, and succeeding ones in Volume XV, 1908, and Volume XXVIII, 1921, the present paper brings the series down to the close of the year 1925, covering a period of over 35 years and embracing four minimum and three maximum epochs of the 11½ year cycles of solar changes. All of the five years' observations were made with a 5½-inch refracting telescope, equatorially mounted, being the same instrument …
Water Softening In The Home, Edward Bartow
Water Softening In The Home, Edward Bartow
Proceedings of the Iowa Academy of Science
In cities or villages the best method of obtaining soft water in the home is to have a city or village supply of soft water. If there is not a city or village supply, plan to get one and use the softest water available. If there is a supply of hard water, have it softened at the source, if it can be done economically. In other words, supplies of soft water must be obtained either from a water originally soft or a natural hard water must be softened. In the United States there are soft water supplies in New York …
Notes On The Reversal Of The Sodium Line, L. B. Spinney
Notes On The Reversal Of The Sodium Line, L. B. Spinney
Proceedings of the Iowa Academy of Science
The reversal of the sodium line may be demonstrated without the use of a slit or a spectroscope. An incandescent lamp having either a carbon or tungsten filament is placed immediately behind a good sodium flame and viewed from a distance of fifteen or twenty inches through a diffraction grating. The first- and second- order spectra, right and left, will both be in view and in the orange-yellow region of each will appear a sharp dark-line image of the filament of the lamp. This image constitutes the dark-line spectrum of the sodium vapor.
The Absorption Of Moisture By Hard Rubber, Geo. E. Thompson
The Absorption Of Moisture By Hard Rubber, Geo. E. Thompson
Proceedings of the Iowa Academy of Science
A study is being made of the effects of relative humidity and electric fields on moisture absorption by hard rubber. A specimen of hard rubber is suspended in a constant temperature box from the beam of a sensitive chainomatic balance. The relative humidity of the box is varied by placing sulphuric acid of various concentrations in the box. The rubber specimen is suspended between two brass electrodes which are attached to a 10,000 volt transformer. At 100 per cent humidity the effect of the electric field is to increase the rate of moisture absorption at first and later to diminish …
The Theory Of The Two-Way Quincke Tube, G. W. Stewart
The Theory Of The Two-Way Quincke Tube, G. W. Stewart
Proceedings of the Iowa Academy of Science
The long known Quincke two-way tube has been assumed to eliminate transmission by interference only at a frequency corresponding to a difference of path of one-half wave length. The author has derived the theory of the action and finds that the ratio of transmitted to incident energy.
A New Analysis Of The Action Of Amsler's Polar Planimeter, George E. Davis
A New Analysis Of The Action Of Amsler's Polar Planimeter, George E. Davis
Proceedings of the Iowa Academy of Science
The theory of Amsler's polar planimeter, as commonly given, leads to the expression A= L h, where A is the area circumscribed, L is the length of the tracer arm, and h is the net distance of translation of the tracer arm in a direction perpendicular to its length. However, it can be shown that the area may also be given by A = L 2 ∅, where ∅ is the net angle through which the tracer arm has rotated about either of its ends. But as the tracer point passes around the area A, the tracer arm does …
Efficiency Of Diffusing Bowls As A Function Of The Lamp Wattage, E. C. Mccracken
Efficiency Of Diffusing Bowls As A Function Of The Lamp Wattage, E. C. Mccracken
Proceedings of the Iowa Academy of Science
It has been generally assumed that the efficiency of a diffusing bowl is independent of the intensity of the source of light providing the color is kept constant. As preliminary experiments indicated that this conclusion was not justified, a special photometer was constructed and measurements were made by eleven independent observers on different types of diffusing bowls and lamps. The results show (1) that the efficiency of a bowl is a function of the lamp wattage, the color of the lamp remaining the same; and (2) that the shape of the efficiency-wattage curve depends upon the color of the source.
The Relation Of Mathematics Aptitude To Other Aptitudes, R. D. Sinclair
The Relation Of Mathematics Aptitude To Other Aptitudes, R. D. Sinclair
Proceedings of the Iowa Academy of Science
The purpose of this study was to determine the relation of mathematics aptitude to aptitude in other subjects. The materials available for the investigation were (1) certain tests that had been taken by the Freshmen upon entering the University in 1925 - tests in Mathematics Aptitude (M.A.) and Mathematics Training (M.T.), English Aptitude (E.A.) and English Training (E.T.), Chemistry Aptitude (C.A.) and Chemistry Training (C.T.), and French Aptitude (F.A.) and French Training (F.T.); (2) High School Content Examinations, Iowa Comprehension Test, and Thorndike Intelligence Test Part 1, Form B; (3) grades made in courses during the Freshman year; and (4) …
A Device For Measuring The Degree Of Aesthetic Sensitivity, Norman C. Meier
A Device For Measuring The Degree Of Aesthetic Sensitivity, Norman C. Meier
Proceedings of the Iowa Academy of Science
Individuals differ greatly in their responses to art situations. The exact nature of this sensitivity is not known but the findings of this investigation indicate that it is more acquired than innate. The highest degree of response comes from those that combine early childhood experience of correct esthetic types with later cognitive acquirements. The function itself is fundamental to artistic production and art criticism.
A Preliminary Survey Of May Beetles In Iowa, H. E. Jaques
A Preliminary Survey Of May Beetles In Iowa, H. E. Jaques
Proceedings of the Iowa Academy of Science
Few insects within our state are of greater economic importance than are the May beetles which in their larval stage as white grubs are serious pests to many growing crops. A normal loss is sustained from them throughout the state each year. The life cycle of at least the most destructive species seems to cover a period of three years and since one brood greatly exceeds the other two in abundance the years of 1921 and 1924 were times when the farmers paid heavy toll to these enemies of grasses, cereals and cultivated crops. This "Brood A" which was responsible …
The Dielectric Properties Of Some Crystals At Radio Frequencies, A. A. Aardal
The Dielectric Properties Of Some Crystals At Radio Frequencies, A. A. Aardal
Proceedings of the Iowa Academy of Science
An attempt has been made to study the dielectric properties of a few crystals at radio frequencies ranging between 50 and 3000 kilo-cycles per second. The properties studied are phase difference, dielectric constant, capacity, resistance, and power factor. It is found that the dielectric constant, the electrical capacity and resistance decreases with the increase in frequencies of electrical oscillation, and that the phase difference and power factor increase with increase in frequencies.
A Simple Derivation Of The Equation For Mean Free Path, George E. Davis
A Simple Derivation Of The Equation For Mean Free Path, George E. Davis
Proceedings of the Iowa Academy of Science
According to simple kinetic theory, in which all the gas molecules but one are considered stationary, the mean free path L is given by L = 1/N π σ2 , where N is the number of molecules per cc. and σ is the molecular diameter. Clausius, considering all molecules to be moving with the mean relative velocity, finds L = 3/4N π σ2. Again, Maxwell, applying his law of velocity distribution, obtains the result L= 1/√2N π σ2. This value found by Maxwell is the one most generally accepted. If we consider it to be correct, …
The Phosgeno-Aluminates Of Lithium Magnesium Potassium And Lead. Molecular Association In Phosgen Solutions, D. M. Birosel
The Phosgeno-Aluminates Of Lithium Magnesium Potassium And Lead. Molecular Association In Phosgen Solutions, D. M. Birosel
Proceedings of the Iowa Academy of Science
The work of Germann and his students has definitely established that Phosgene is a Mother Solvent for a system of acids, bases, and salts. The acids are capable of reacting with metals and bases of this system to form salts. By neutralizing phosgenoaluminic acid with the anhydrous halides of Lithium, Magnesium, Potassium and Lead, their respective salts are obtained. The Potassium and Lead salts are difficult to work with because they form crusts at the end of the Faraday tubes. Lithium and Magneseum form LiAlCl4 and Mg2Al5Cl19 respectively. By a study of the pressure-concentration …
The Phosphorescence Of Fused Quartz, A. C. Bailey
The Phosphorescence Of Fused Quartz, A. C. Bailey
Proceedings of the Iowa Academy of Science
Experiments performed here corroborate the report of Drummond and Webster that fused quartz can be activated to phosphorescence by being irradiated with ultra violet light from a quartz mercury vapor lamp. It is also found that the fused quartz is thermoluminescent. The radiations emitted from the phosphorescent and thermoluminescent quartz appear to be confined largely, if not completely, to the visible region. These radiations, however, at ordinary room temperatures, are of such low intensity as to be invisible to the eye.
Verle Mcfarland Diary, Verle Mcfarland
Verle Mcfarland Diary, Verle Mcfarland
Iowa Book Gallery
A 1926 diary of Verle McFarland (Shanks), a student at Iowa State Teachers College and a teacher in one-room schoolhouses in Lucas County, Iowa, in the 1920s and 1930s.
Atlas Of Black Hawk County, Iowa, Andersen Publishing Co.
Atlas Of Black Hawk County, Iowa, Andersen Publishing Co.
Iowa Book Gallery
Maps and directories for Black Hawk County, Iowa and each of its townships. Also includes a world atlas and U.S. census population figures.
The Hokum, V1n2, 1926, Iowa State Teachers College
The Hokum, V1n2, 1926, Iowa State Teachers College
Hokum
The Hokum (v.1, no.2, 1926) is an early entertainment magazine written and created by students at the Iowa State Teachers College (now the University of Northern Iowa).
Fifty Years At The Teachers College, David Sands Wright
Fifty Years At The Teachers College, David Sands Wright
Iowa Book Gallery
A history of the Iowa State Teachers College, later known as the University of Northern Iowa.
In Memoriam: Philip Sprong; Walter Scott Hendrixson; Clyde Leslie Winter
In Memoriam: Philip Sprong; Walter Scott Hendrixson; Clyde Leslie Winter
Proceedings of the Iowa Academy of Science
No abstract provided.
The Address Of The President - The Ministry Of Science, R. I. Cratty
The Address Of The President - The Ministry Of Science, R. I. Cratty
Proceedings of the Iowa Academy of Science
We are living in a very progressive age - one which when compared with that of our forebears, is filled with advantages for our welfare and enjoyment that challenges the attention of every thoughtful person. That knowledge is power was never a more self-evident truth than it is today, and science, which is simply classified knowledge, is every day coming more closely in touch with human lives, and ministers to us in innumerable ways undreamed of a century ago. Just how great our debt is for all this it is difficult to say. Captain Roald Amundson, that modern Viking whom …
The Present Tendencies In The Bacteriological Examination Of Water, Jack J. Hinman, Jr.
The Present Tendencies In The Bacteriological Examination Of Water, Jack J. Hinman, Jr.
Proceedings of the Iowa Academy of Science
No abstract provided.
Preliminary Note On The Sterilization Of Seeds Of The Leguminosae With Hydrogen Peroxide, Rudger H. Walker, Lewis W. Erdman
Preliminary Note On The Sterilization Of Seeds Of The Leguminosae With Hydrogen Peroxide, Rudger H. Walker, Lewis W. Erdman
Proceedings of the Iowa Academy of Science
In the scientific study of many bacteriological problems it is necessary to deal with pure cultures of the organism with which the worker is interested. This has been true in our studies on the nodule producing organisms of leguminous plants. Before any morphological or physiological studies are made on these organisms they should be tested on the host plant for their inoculating ability, and in order to do this all possible chances for contamination by other organisms must be eliminated. If, in testing out a certain culture for its inoculating ability on the host plant, the plants were grown under …
Studies On Germination Of Trees And Woody Plants, Continued, L. H. Pammel, Charlotte M. King
Studies On Germination Of Trees And Woody Plants, Continued, L. H. Pammel, Charlotte M. King
Proceedings of the Iowa Academy of Science
For continuation of our studies of germination, there were collected in the fall of 1925 seeds of about 50 species of trees and woody plants. The source of these seeds is in large part local, with a number sent in by the senior author, from Arizona and California. These seeds were planted in the greenhouse at time of collection. Duplicates of about 20 species were held out of doors for stratifying, under natural conditions. These were removed to the greenhouse March 25, 1926. At time of April 20, only 2 species had germinated, Pinus Lambertiana and Caragana arborescens.