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The Address Of The President - The Cosmology Of The Universe, D. W. Morehouse

Proceedings of the Iowa Academy of Science

Astronomy is the original science. Its scope comprehends all the physical sciences - geology, physics, chemistry - and even the natural sciences. All borrow from it, and in turn contribute to astronomical knowledge. Moreover, from the very beginning, the study of astronomy has been inseparably connected with philosophy and religious speculation. For its theme - its age-long objective - has been a true world concept. I quote: "Back of every religion, and of every philosophy or science, worthy of the name, lies a world-view, a concept in which are included all localities and all beings supposed in that religion or …

Deductions From The Occurrence And Character Of Two Large Quartzose Conglomerate Boulders Of Unknown Origin Found In The Kansan Drift Sheet At Centerville, Iowa, Ben H. Wilson

Proceedings of the Iowa Academy of Science

On a lawn at No. 629 West Maple Avenue, in Centerville, Iowa, are located two large quartzose conglomerate boulders which are of more than usual interest. These were removed from the glacial till during the process of excavating for the cellar under the dwelling now situated on the same lot and when found were said to be buried beneath several feet of drift material.

Hall Effect And Specific Resistance In Evaporated Films Of Silver, Copper And Iron, J. C. Steinberg

Proceedings of the Iowa Academy of Science

Previous investigators have found the specific resistance a constant for metallic films, until the thickness becomes comparable with particle dimensions, at which thickness the resistance becomes very great. Wait found the resistivity of chemically deposited silver films, whose thicknesses were greater than the above mentioned critical thickness, to be only slightly greater than that of the bulk metal. He found the Hall Effect in these films, as well as in films whose thicknesses were less than the critical thickness, to be the same as that of bulk silver. On the conception that the substance in a film consists of granules …

Simultaneous Fast And Slow Drum Records Of Fatigue, Francis Marsh Baldwin

Proceedings of the Iowa Academy of Science

The essential details of fatigue processes as they develop in a properly prepared protoplasmic system like that of a frog muscle, are conveniently transcribed by the writing lever either upon a kymograph drum revolving comparatively rapidly, or one going very slowly and these records furnish data for subsequent analysis. In each procedure some facts' are obtained as to amplitude, enhancing and diminution of responses under a given rate of stimulation and under certain physical and physiological conditions, but unfortunately neither method alone suffices for the proper analysis of the whole process. Although details of mechanical devices differ somewhat in the …

Chance In Development As A Cause Of Variation, P. W. Whiting

Proceedings of the Iowa Academy of Science

Variation is ordinarily considered as due to internal hereditary factors interacting with external environmental factors during development. In experimental work with a parasitic wasp considerable variation has been found in certain pure-bred stocks kept at certain constant environmental conditions. Either at other constant environmental conditions or in other pure-bred stocks this variation does not occur. Variation appearing under uniform conditions of heredity and environment is considered as due to slight irregularities of division and distribution of cells during embryology and to other more or less intangible factors of development. Individual variation resulting from chance in development is on the average …

The Founders Of The Art Of Plant Breeding, Fred C. Werkenthin

Proceedings of the Iowa Academy of Science

The paper by Prof. Werkenthin on History of Plant Breeding was one of the assigned topics in the course given at Iowa State College on the History of Botany. The subject matter is so admirably treated that it has seemed wise to publish this as a posthumous paper. It was the last paper prepared by him, finished only a few weeks before he was taken sick.

The Structure And Development Of The Seed Coat And Cause Of Delayed Germination In Mellilotus Alba, J. N. Martin

Proceedings of the Iowa Academy of Science

The epidermis of the ovules forms the much elongated cells, known as the Malpighian cells of the seed coat. The outer walls of the Malpighian cells are much thickened and are composed of layers differing in physical properties. One of these layers is the light line which in most seeds is impervious to water until it is modified by weathering or by some artificial means. The light line is apparently only more compact cellulose for it hydrates quickly in water at 80° C. and then gives a distinct cellulose reaction and is permeable to water. The action of the weather …

Table Of Contents

Proceedings of the Iowa Academy of Science

No abstract provided.

Solubility And Polarity, Wm. Kunerth

Proceedings of the Iowa Academy of Science

Since the phenomenon of solubility is one of such common occurrence and universal familiarity, it is no wonder that a great many attempts have been made to learn the cause of it. The molecular weight of solute and solvent, the dielectric constants, the size of the molecules concerned, the surface tensions of the components, adsorption, the vapor pressure above the solution, the magnitude of Van der Waal's a and b for the components, their internal pressures · as determined by a great many different methods - all these and many other avenues of approach have been used, only to be …

A Comparison Of Intensities Required Under Direct And Under Indirect Lighting Systems, Wm. Kunerth

Proceedings of the Iowa Academy of Science

Although artificial indirect lighting dates back twenty-five years or more, it was not very extensively patronized until after 1906 when the advent of the more efficient Mazda B lamp made its commercial use possible. At once comparisons were made between the direct and the indirect systems on various points.

A Chemical Classification Of The Activities Of Soil Microorganisms, Paul Emerson

Proceedings of the Iowa Academy of Science

At the present time it may be said that the process of decomposition with its resultant complex chemical changes taking place in the soil is controlled primarily by the activities of micro-organisms and that Soil Fertility is mainly dependent upon these microscopic forms.

The Alumni News Letter, V5n4, October 1, 1921, Iowa State Teachers College

The Alumni News Letter

Contains news of the College and its alumni.

The Alumni News Letter, V5n3, July 1, 1921, Iowa State Teachers College

The Alumni News Letter

Contains news of the College and its alumni.

Spring Term Commencement [Program], May 31, 1921, Iowa State Teachers College

UNI Commencement Programs

The program of the commencement ceremonies, including a list of institutional leadership, a list of the departments by college, awards given at the ceremonies, and a list of undergraduate and graduate degree candidates.

The Alumni News Letter, V5n2, April 1, 1921, Iowa State Teachers College

The Alumni News Letter

Contains news of the College and its alumni.

Winter Term Commencement [Program], March 8, 1921, Iowa State Teachers College

UNI Commencement Programs

The program of the commencement ceremonies, including a list of institutional leadership, a list of the departments by college, awards given at the ceremonies, and a list of undergraduate and graduate degree candidates.

Methods Of Teaching Parasitology, Herbert R. Werner

Proceedings of the Iowa Academy of Science

The fact that animal parasites are important as disease producing agents has been known for a great many years. Thought, consideration, study, and emphasis on the question of parasitism have come in waves; at times it was looked upon as one of the most important factors to be dealt with, while at other times or periods it has received almost no attention and parasites have been looked upon as more or less unimportant as disease producing agents. But the necessity for the protection of our livestock from disease has grown, being governed largely by the supply and demand, together with …

1921 Old Gold, Iowa State Teachers College

UNI Yearbooks

The student yearbook of the Iowa State Teachers College, later known as the University of Northern Iowa.

The Alumni News Letter, V5n1, January 1, 1921, Iowa State Teachers College

The Alumni News Letter

Contains news of the College and its alumni.

Hall Effect In Thin Silver Films, J. C. Steinberg

Proceedings of the Iowa Academy of Science

The Hall Effect as a function of thickness has been investigated in chemically deposited films of silver, of thickness ranging from 40 to 200 millimicrons, and the Hall Coefficient found to be independent of both magnetic field, for fields up to 20000 Gauss, and thickness. The specific resistance of the same films increases as much as 200 per cent for some of the thinner films. These results are in good agreement with those obtained by Dr. G. R. Wait last year.

Table Of Contents

Proceedings of the Iowa Academy of Science

No abstract provided.

The Coefficient Of Simple Rigidity And Young's Modulus For Hexagonal Crystals Of Selenium, L. P. Sieg, R. F. Miller

Proceedings of the Iowa Academy of Science

Elastic constants determined from drawn wires are of considerable practical use, but they are not very illuminating on the subject of the structure of matter. A drawn wire is a heterogeneous mass of matter in crystalline and amorphous states, with never any regularity in composition or of crystalline structure. In fact the elastic constants so determined are not so much characteristic of the substance, say copper, as of the particular physical state of that substance. If, however, one could employ an isolated crystal of a simple elementary substance, he ought to be able to determine the elastic constants of the …

Some Pleistocene Exposures In Des Moines, James H. Lees

Proceedings of the Iowa Academy of Science

In the early spring of 1921 as the writer was examining the face of the bluff bounding the north side of the Des Moines valley just below the Capitol grounds he noticed, on the west side of the entrance to a ravine between Southeast 13th and 14th streets, where the State operated a small drift coal mine for some time, a section of Pleistocene material above the Coal Measures sandstone, which seemed to present features of some interest. Closer inspection showed the probable presence of two drift sheets and since the superposed evidence of successive invasions of the continental glaciers …

College Catalog And Circular 1921, Iowa State Teachers College

UNI Programs and Courses Catalogs

Table of Contents

Calendar for 1921-1922 ... 5
Officers of Administration and Instruction ... 6
General Information ... 32
Residence, Student Health, Assembly ... 35
Expenses and Fees ... 36
Free Scholarships ... 38
Extension Service ... 38
College Organizations ... 39
Faculty Organizations ... 39
Training in Actual Teaching ... 40
Public Lectures and Entertainments ... 40
Boarding and Lodging ... 40
Employment of Students ... 42
Twelve Weeks Normal Training ... 42
School Credits in Lieu of Certificate Examinations ... 42
Examinations for Teachers Certificates ... 42
Department Certificates ... 42
Bureau of Recommendations ... 42
Degree Curriculums …

Measurements Of The Amplitude Of Vibration Of The Diaphragm Of The Hewlett Tone Generator, C. E. Lane

Proceedings of the Iowa Academy of Science

The "New Tone Generator" designed by Dr. C. W. Hewlett promises to be a very valuable instrument for use as a precision source of sound. The operation of the instrument has been investigated mathematically by its designer and a method is given for calculating the amplitude of vibration of its diaphragm from the electrical input. The writer herein describes a method whereby it has been possible to make actual measurements of the amplitude by mechanical means for comparison with the calculated amplitudes. The tone generator was used in a vacuum tube oscillatory circuit from which the desired frequencies of alternating …

Corn Oil Cake Meal For Growing And Fattening Pigs, John M. Evvard, Russell Dunn

Proceedings of the Iowa Academy of Science

Corn oil cake meal is really a residue of the germs of corn grain which remains after most of the oil is extracted therefrom. The particular corn oil cake meal which we used in our test is a by-product from the manufacture of glucose. These four main products are made from the corn grain: Glucose, corn oil, gluten feed, and corn oil cake meal. It is with the latter that we are to deal.

In Memoriam: E. W. Stanton, L. H. Pammel

Proceedings of the Iowa Academy of Science

No abstract provided.

A Laboratory Optical Pyrometer: Notes On Its Design And Operation, Wm. Schriever

Proceedings of the Iowa Academy of Science

The writer was confronted with the problem of measuring the temperature of a tungsten wire enclosed in an evacuated tube. A thermocouple could not be used because it would be certain to apply unknown torques to the wire and also to disturb the temperature distribution along the wire. An optical or radiation method of temperature measurement would overcome both of these difficulties. An optical pyrometer suitable for accurate temperature determinations and flexible enough to be of general use in a physical laboratory is not on the market at the present time. This led the writer to the task of designing …

Measurements Of The Minimum Audible Intensity Of Sound For Tones Of High Frequency, C. E. Lane

Proceedings of the Iowa Academy of Science

Many investigators have worked on the problem of determining the minimum amount of sound energy necessary for audible perception, but most of the investigations have been concerned with sounds of ordinary frequency and very little attempt has been made to make such a determination in absolute units near the upper limit of the range of audition. The mechanical difficulty of securing tones of sufficient intensity at these high frequencies is great, and, furthermore, it is not so easy to ascertain the amount of sound energy given out from the sounding apparatus at these values of frequency as at lower values.

The Tactual Analog Of Stroboscopy, L. E. Dodd

Proceedings of the Iowa Academy of Science

The subject of coincidences has application in stroboscopy, or the stroboscopic effect, in vision, and in the phenomenon of musical beats in audition. By means of a suitable mechanical device it applies also to the tactual sense. There may thus be produced tactual, as well as musical and optical beats.