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A Light-Colored Zone Of Subsoil Southern Iowa, W. G. Baker

Proceedings of the Iowa Academy of Science

In the excavations of the new primary road cuts during the past three years many cross-sections of the soils of southern Iowa have been exposed to view. One zone of soil which is particularly noticeable occurs overlying the Kansan till. The zone is a light-colored layer and the leached or unleached loess, as the case may be rests upon it, while the gravels of the Kansan, with few exceptions lie under it. The reddish ferreto zone in connection with these gravels gives a contrast in colors which makes the light colored zone easy to distinguish in the cross-sections along many …

The Deep Water-Well At Brighton, J. M. Lindly

Proceedings of the Iowa Academy of Science

The town of Brighton is situated in the southwestern part of Washington County, Iowa, and according to the census of 1920 it has a population of 1,014. During the year 1919, the town installed water works and a sewer system with six miles of ditches and a disposal plant. The supply of water was from a well about sixty feet deep. This well failed to yield a sufficient supply of water, and resort was had to the well at the canning factory. This arrangement was not altogether satisfactory, particularly during the canning season when it, too, failed to yield a …

A Method For The Production Of Longitudinal Sound Vibrations In A Rod, William D. Crozier

Proceedings of the Iowa Academy of Science

In connection with some work being done in the testing of acoustic wave filters in solid media, a method has been developed for the production of longitudinal sound vibrations in a rod. Electrical oscillations are generated in a vacuum tube oscillator, pass through two stages of power amplification, and are used as the input to a special oscillator attached to the end of the rod. This oscillator is similar in principle and construction to the Fessenden oscillator used in submarine sound signaling. Vibrations which have a fair purity of tone, and which have a considerable intensity over a wide range …

The Optical Constants Of Crystals Of Selenium Tellurium For Wave-Lengths From 3000 To 5000 A, R. F. Miller

Proceedings of the Iowa Academy of Science

The measurements were made by a photographic method, for two positions of the crystal (1) with the optic axis parallel, and (2) with the axis perpendicular, to the plane of incidence. Two sets of optical constants were found for each substance. For selenium, in the parallel position the index of refraction was found to vary from 3.4 to 4.4, and the reflecting power from 0.38 to 0.46; in the perpendicular position the index varies from 2.3 to 3.1, and the reflecting power from 0.41 to 0.34. For tellurium, in the parallel position the index varies from 1.9 to 2.9, and …

The Hall Effect And Specific Resistance In Evaporated Films Of Nickel, Cobalt, Palladium And Platinum, H. B. Peacock

Proceedings of the Iowa Academy of Science

Steinberg has shown that in the case of a thin film of metal formed by evaporation from a heated filament in a high vacuum the specific resistance and Hall coefficient are not the same as for the bulk metal. The metals investigated were silver, copper and iron, and in all of these the specific resistance was found to be about 1000% greater than in the metals in bulk. The Hall coefficients were slightly smaller for silver and copper than for the bulk metals, but for iron this coefficient was about 600% greater than the value generally accepted for iron. Also, …

The Intrinsic Intensity And Percent Of Polarization Of Light Transmitted Through Deep Slits, L. P. Sieg

Proceedings of the Iowa Academy of Science

It is assumed that the light incident upon the first opening of a slit between various metals is diffracted in the usual manner, and finally emerges from the far end of the slit after repeated reflections. The reflecting coefficients of the various metals considered are calculated for the proper angles of incidence from a knowledge of the index of refraction of the metal, and from its coefficient of absorption. In view of the fact that the coefficients of reflections for light possessing an electric vector perpendicular are much larger than for light with the electric vector parallel to the plane …

The Effect Of The Material Composing The Sides Of Deep Slits On The Intrinsic Intensity Of Light Transmitted Through The Slits, Clarence R. Smith

Proceedings of the Iowa Academy of Science

It is shown that differences in intensity of the light transmitted by a narrow, deep slit are produced by changing the material of the sides though other conditions are kept constant. With a pair of optically plane surfaces of each of the metals, steel, nickel, gold, silver and copper, a slit was prepared which could be varied in width while the depth remained constant. For each of these metals a curve was prepared showing the variation of transmitted light intensity with change in width of slit. Comparison of the curves for the various metals shows a fairly close agreement for …

The Action Of A Helmolts Resonator In A Branch Line, G. W. Stewart

Proceedings of the Iowa Academy of Science

The general impression of a Helmholtz resonator is that, since its dissipation is small, its tuning is fairly sharp. It is noted with some surprise, therefore, that when used as a side branch in an acoustic transmission line it affects the transmission over a wide range of frequencies. The theory, derived from the general case in the preceding abstract has been checked by experiment with resonators of varying dimensions and the theory verified to a very satisfactory degree.

Theory Of Megaphones And Receiving Horns, G. W. Stewart, G. R. Butz

Proceedings of the Iowa Academy of Science

In 1919, A. G. Webster published a theory of the action of horns used as receivers. Recent development has given an increased interest in the megaphone. Webster's theory may be modified to cover the case of the megaphone, assuming the constancy of the acoustic point impedance of the horn at the source. The result obtained is that the emitted energies at different frequencies are related as are the values of [(ad-bc)/(a-cz₂)]² wherein a, b, c and d, have the values specified in Webster's theory and z2=δa²k² (ki/2π-1/c₀), k being 2π …

The M Absorption Limits Of The Tungsten X-Ray Spectrum, R. V. Zumstein

Proceedings of the Iowa Academy of Science

The x-ray spectrum of tungsten has been investigated from 7 to 3 Angstrom Units, using a metal x-ray tube and a vacuum spectrometer.

A Note On Daylight Requirement, Wm. Kunerth

Proceedings of the Iowa Academy of Science

Two years ago the author read a short paper in which he gave the intensity of illumination required when direct lighting is used as compared with what is required when indirect lighting is employed. Experimental results were given based on the average obtained from 26 college seniors. The data showed that 2.8 ft. candles were desirable for reading by direct lighting and 4.0 ft. candles by indirect lighting, both being median value. Only artificial light was used.

The Differential Death-Rate Of The Sexes Among Animals, With A Suggested Explanation, S. W. Geiser

Proceedings of the Iowa Academy of Science

It has been conclusively demonstrated in certain mammals, fishes, arthropods, nematodes and mollusks that the female sex has a greater longevity than the male. (Geiser, '21, '23; et al.) Longevity within the species appears to be inherited in the manner of "blending inheritance," i.e., its mode of inheritance is probably through a series of multiple gametic factors. (Beeton & Pearson, '00, '01; Pearl, Parker & Gonzalez, '23; Gonzalez, '23.)

Results Of The Testing Program Given At Iowa State College, Nora M. Klise

Proceedings of the Iowa Academy of Science

The results given in this report were based upon a study of 368 Home Economics students who had been given mental tests in the spring and fall of 1919. 145 of the 368 had been given Alpha mental test, and 223, Thorndike. High school records were available for 339 of them. The object was to study criteria for prediction of college scholarship. Alpha had the highest correlation with college average, 0.45 as compared with 0.34 for high school with college average, and 0.38 for Thorndike with college average. English had the highest correlation, with college average (0.59) of any individual …

Three Different Types Of Genetic Sterility In The Parasitic Wasp, Habrobracon, P. W. Whiting

Proceedings of the Iowa Academy of Science

Almost complete sterility may be induced by imperfect fertilization. Resulting male offspring very rarely produce daughters which are almost always sterile. Complete sterility of males due to lack of external genitalia exists in one strain, which is reproduced from sisters and fertile brothers. A previously fertile strain mutated so that females lay inviable eggs. Rarely an egg will hatch and from the resulting insect the strain is perpetuated. Males of this strain are of normal fertility.

Two Generations Of Selection With Reference To The Inheritance Of Scurvy Resistance In Guinea-Pigs, W. V. Lambert

Proceedings of the Iowa Academy of Science

Selection over two generations for increased and decreased resistance to scurvy in guinea-pigs has failed to produce conclusive evidence that the individual variations noted in resistance toward scurvy are inherited. An analysis of the effect of age, weight, and vigor as influencing resistance is presented and it is concluded that these factors, within the limits represented in the data, have not influenced the results. The results for the first generation of selection indicate a pronounced influence, but in the second generation the difference between the minus and plus selections is not significant.

Snake Notes, J. E. Guthrie

Proceedings of the Iowa Academy of Science

There is probably no inborn snake-dread. Snake species and personalities differ widely among themselves. A captive rattlesnake shed four skins and got four rattles in a year. Poisonous snakes shed and swallow their poison fangs. About 1600 rattlesnakes were presented for bounties last year in seven Iowa counties. Virginia elegans Kenn. is reported as new for Iowa. Figures of a double-headed garter snake and of a two-headed bullsnake embryo are given.

Birds Of Wapello County, Iowa, Chas. J. Spiker

Proceedings of the Iowa Academy of Science

Wapello County is located in the southeast part of Iowa with one county between it and the Iowa-Missouri line and three counties east of it between it and the Mississippi river. It is bounded on the north by Mahaska and Keokuk Counties, on the east by Jefferson County, on the south by Davis County, and on the west by Monroe County. Its county seat is Ottumwa. The Des Moines River flows diagonally across the county from northwest to southeast. It is quite heavily timbered for most of its course, affording an excellent route for the migration of birds common to …

Holbrook's North American Herpetology. First Edition., B. Shimek

Proceedings of the Iowa Academy of Science

Some years ago the late Dr. Theodore Gill published an article in which he announced the discovery of a fourth volume of the first edition of Holbrook's "North American Herpetology" (1840), of which but three volumes had been known. This copy was found in the library of the Academy of Natural Sciences of Philadelphia, and Dr. Gill's article was based on a report of its contents furnished by Mr. Witmer Stone.

Keeping Iowa's Waters Pure, George Bennett

Proceedings of the Iowa Academy of Science

When one quietly and sanely considers the great movement embraced by the words "Wild Life Conservation," in all its ramifications, what the past reveals, its influence on the present and connection with the future, the intelligent student of world economy will feel amazed and stupefied at the situation as it looms before him. He will put a question to himself as to where he has been, and what he has been doing during all this orgy of world rapine and world desolation, a question that he can much more easily ask than answer.

The Lateral Line Organs Of The Shovel-Nose Sturgeon, Distribution And Innervation, H. W. Norris

Proceedings of the Iowa Academy of Science

The findings of Allis ('04) are verified for the most part. Two series of lateral line sense organs are represented: canal organs and sensory pits ("nerve sacs"). There is a very close correspondence with the Paddlefish in the arrangement of the canals and the grouping of the sensory pits.

A Study Of The Movements Of The Empty Stomach In The Mollusca, T. L. Patterson

Proceedings of the Iowa Academy of Science

Our knowledge concerning the variations of the gastric activity in the various animal groups is still very incomplete and this is notably true in the case of the invertebrates. The present investigation is limited to two species of marine and one specie of terrestrial mollusca, which in so far as I am aware, represents the first study to be made on the movements of the empty stomach in any of the invertebrates.

Fall Term Commencement [Program], December 4, 1923, 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, V7n4, October 1, 1923, Iowa State Teachers College

The Alumni News Letter

Contains news of the College and its alumni.

Iowa State Teachers College Program Of Recitations, Fall 1923, Iowa State Teachers College

UNI Schedule of Classes

A listing and schedule of the courses being taught as well as policies and procedures concerning attending classes at the Iowa State Teachers College.

Summer Term Commencement [Program], August 23, 1923, 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, V7n3, July 1, 1923, Iowa State Teachers College

The Alumni News Letter

Contains news of the College and its alumni.

Spring Term Commencement [Program], June 5, 1923, 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, V7n2, April 1, 1923, Iowa State Teachers College

The Alumni News Letter

Contains news of the College and its alumni.

Winter Term Commencement [Program], March 13, 1923, 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.

Demonstration Of The Variable Character Of The Vowel E, G. W. Stewart

Proceedings of the Iowa Academy of Science

10. Demonstration of the variable

Professor D. C. Miller's analysis of the sustained vowel e as in meet indicates two important resonance regions surrounding the frequencies 308 and 3100 d. v. That the vowel did not have the same character throughout was evident from his curves. The present demonstration is to exhibit to an audience the fact of the changing character and something as to its nature. Syllables containing the vowel are spoken through an acoustic filter cutting off above 3000 d. v. and then above 2400 d. v. The vowel in eat cannot be recognized in either case, whereas …