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The Effect Of Light Intensity On Tissue Fluids In Wheat, W. F. Loehwing Jan 1930

The Effect Of Light Intensity On Tissue Fluids In Wheat, W. F. Loehwing

Proceedings of the Iowa Academy of Science

Foliar chlorosis was observed to occur frequently during periods of strong insolation in grain plants growing humus soils to which lime had been added to correct acidity. An experiment was undertaken to determine the reasons for the increasing prevalence of chlorosis during periods of clear, sunny weather.

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The Influence Of Position On The Apparent Position, Size And Form Of Angles, William B. Collins Jan 1930

The Influence Of Position On The Apparent Position, Size And Form Of Angles, William B. Collins

Proceedings of the Iowa Academy of Science

The angles were drawn with black india ink on white cards 10 cm. square and exhibited to the observer in the Michotte tachistoscope. The observer reproduced the angles with a pencil on a piece of white paper, 10 cm. square. The position of the reproduced legs of the angle was then measured. The size of the angle and the position of the bisector were computed subsequently. Position was measured in terms of a circular protractor placed in a vertical plane and rotated until 0° was uppermost. The protractor was also turned so as to read in the clockwise direction. Twelve …

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A Study Of A Class Of Twenty Failing Students At Iowa State College, J. E. Evans Jan 1930

A Study Of A Class Of Twenty Failing Students At Iowa State College, J. E. Evans

Proceedings of the Iowa Academy of Science

During the winter quarter of 1930 fifty men engineering students from the freshman class of 1929 were registered in a class in which methods of study were discussed. This class met twice a week during the term. At the close of the fall term these students had attracted the attention of the scholarship committee because of poor work. All students in the group had failed or conditioned part of their work. If the scholarship committee had followed its regular procedure these students would have been eliminated from the college because of poor academic work.

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Dimethyl-Alpha-Naphthylamine For The Determination Of Bacterial Reduction Of Nitrates, C. H. Werkman Jan 1930

Dimethyl-Alpha-Naphthylamine For The Determination Of Bacterial Reduction Of Nitrates, C. H. Werkman

Proceedings of the Iowa Academy of Science

The alpha-naphthylamine-sulphanilic acid test is widely employed for the detection of reduction of nitrates to nitrites by bacteria. The test has the disadvantage that the reel coloration produced in the presence of the nitrite ion appears for only a few seconds and then fades in cultures of organisms in which a relatively high concentration of nitrite occurs. Frequently in our work it is necessary to test considerable numbers of cultures at one time. Fading makes the results unreliable and cultures having a relatively high concentration of nitrite may be recorded as negative. A second difficulty experienced with the test is …

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Biology In High Schools Of Iowa, George O. Hendrickson Jan 1930

Biology In High Schools Of Iowa, George O. Hendrickson

Proceedings of the Iowa Academy of Science

Within recent years Zoology and Botany as separate subjects have nearly disappeared from the curricula of the public High Schools of Iowa. A course known as Biology has taken their places. In an attempt to learn the nature of High School Biology the author secured sample textbooks, laboratory manuals and figures concerning adoptions from the leading publishers of school books.

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A Spirifer Disjunctus Fauna In Iowa, Lowell Robert Laudon Jan 1930

A Spirifer Disjunctus Fauna In Iowa, Lowell Robert Laudon

Proceedings of the Iowa Academy of Science

The Sheffield formation is found in north central Iowa lying unconformably on the Owen limestone of Upper Devonian age and unconformably below the Hampton formation of Kinderhook age. The region in which the Sheffield is best exposed is in northeastern Franklin County within the area of the Iowan drift. The drift is thin enough in this area to reflect the underlying rock surface. The soft nature of the Sheffield material has allowed the streams to curve out a mature rolling topography in this portion of the county. Because of the thin Iowan drift the exposures of the Sheffield are found …

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A Study Of Phosphorescent Zinc Sulphide Screens And Radioactivity Under Extremely High Pressure, Thomas C. Poulter, Harold Mccomb Jan 1930

A Study Of Phosphorescent Zinc Sulphide Screens And Radioactivity Under Extremely High Pressure, Thomas C. Poulter, Harold Mccomb

Proceedings of the Iowa Academy of Science

For a study of the effect of pressure on fluorescent zinc sulphide screens, an arrangement very similar to that used in the preceeding paper was employed. In this case the fluorescent zinc sulphide was mounted on the inner surface of the pressure window with a transparent cement.

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1930 Old Gold, Iowa State Teachers College Jan 1930

1930 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.

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Motion, L. Begeman Jan 1930

Motion, L. Begeman

Science Bulletin

Motion is a general property of matter. There is no rest in the absolute sense. An object at rest with reference to the earth 's surface is in rapid motion with reference to the earth's axis of rotation just as a person may be at rest in a Pullman car and at the same time be in rapid motion with reference to the ground. All divisions of matter, - masses, molecules, atoms, protons, and electrons are moving relatively all of the time.

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Astronomy, E. J. Cable Jan 1930

Astronomy, E. J. Cable

Science Bulletin

In the field of general science, astronomy offers projects for practical as well as very useful knowledge. One of the greatest values is its appeal to the intellect. Astronomy attempts to unravel the secrets of nature, not only on our planet, but also in the vastness of space around us that is within reach of man's powerful instruments. It acquaints man with what is going on around him as well as with what is happening in regions far removed from everyday experiences and personal contacts. Astronomy tries to make man feel "comfortable" and at "home" in his universe.

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Further Studies On The Nitrate Assimilating Power Of Soils, Ray A. Pendleton, Frederick B. Smith Jan 1930

Further Studies On The Nitrate Assimilating Power Of Soils, Ray A. Pendleton, Frederick B. Smith

Proceedings of the Iowa Academy of Science

In a paper read at the meeting last year it was pointed out that when a soluble form of organic matter was added to soils which were incubated in tumblers, a considerable quantity of nitrate nitrogen could be used by the micro-organisms of the soil. The amount of nitrate nitrogen assimilated was in a measure determined by the amount of nitrate present at the beginning, the form and amount of organic matter used, and the length of incubation period. Two percent of straw furnished sufficient carbon for the assimilation of 10 mgm. per 100 gms. of soil in one week, …

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Development Of The Vascular System Of Corn, A. L. Hershey, J. N. Martin Jan 1930

Development Of The Vascular System Of Corn, A. L. Hershey, J. N. Martin

Proceedings of the Iowa Academy of Science

The body of a plant is a cooperative system of cells, tissues, and organs. Yield is a function of the cooperation of these structures. Viewing the plant from this angle a knowledge of the kinds, relationships and time of formation of tissues of Zea mays is essential for an understanding of the factors which influence yield.

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Some Weeds Of Iowa, Florida, Lower Rio Grande Valley, Cuba And India Compared, L. H. Pammel Jan 1930

Some Weeds Of Iowa, Florida, Lower Rio Grande Valley, Cuba And India Compared, L. H. Pammel

Proceedings of the Iowa Academy of Science

The question of weeds and the migration of plants is an interesting phase of botany. I have discussed this subject quite fully in several papers on weed migration.

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The Anatomy Of The Crowns And Roots Of The Annual And Biennial White Sweet Clover Compared, J. N. Martin Jan 1930

The Anatomy Of The Crowns And Roots Of The Annual And Biennial White Sweet Clover Compared, J. N. Martin

Proceedings of the Iowa Academy of Science

In case of the annual, all structures die at the end of first season's growth. In the biennial only the aerial shoot dies at end of first season's growth. The root and the crown of the biennial prepare, during the first season, for the second season's growth which consists chiefly in the development and fruiting of the flowering shoots that are present on the crown but held in check during first season's growth.

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The Chlorine Derivatives Of Vanillin, L. Chas. Raiford, J. G. Lichty Jan 1930

The Chlorine Derivatives Of Vanillin, L. Chas. Raiford, J. G. Lichty

Proceedings of the Iowa Academy of Science

The purpose of this work was to complete the possible list of chlorine derivatives of vanillin, and to use these products in testing further the theory that the presence of acidic substituents favors the formation of stereoisomeric aldoximes.

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Statistical Control Of A Grading System, George W. Snedecor Jan 1930

Statistical Control Of A Grading System, George W. Snedecor

Proceedings of the Iowa Academy of Science

"Statistical Control" is a phrase which is very popular in business circles. What does it mean? Let us examine two types, the statistical control of the quality of a manufactured product, and the statistical control of a purchasing department. In the former case, over a sufficient period of time, records are made of the number of defects per 1000 (say) found in the product manufactured. From these records statistical standards are set up consisting of the averages and distributions of the occurrence of defects. By comparing any subsequent sample with such standards, the statistician is able to assert that the …

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The Disruption Of Potentials Within A Raw Potato Under Constant Applied Voltage, E. C. Mccracken Jan 1930

The Disruption Of Potentials Within A Raw Potato Under Constant Applied Voltage, E. C. Mccracken

Proceedings of the Iowa Academy of Science

Uniformly shaped sections of raw potatoes were placed between parallel plane electrodes and subjected to a constant potential. The potential drops existing between one electrode and various points in the potatoes were measured. The equi-potential surfaces were found to be planes parallel to the surface of the terminal electrodes. The potentials of these planes were found to vary with time and previous passage of current. The relative size of the probing electrodes used influenced the shape of the potential distribution curves.

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The Buffalo In Iowa, L. H. Pammel Jan 1930

The Buffalo In Iowa, L. H. Pammel

Proceedings of the Iowa Academy of Science

The purpose of this study is to prove that the buffalo once occurred in Iowa because there are many Iowans who deny the presence of this noble animal in the state. Much data was collected.

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The Development Of The Ovary And Oviduct Of The Gold Fish, Frank A. Stromsten Jan 1930

The Development Of The Ovary And Oviduct Of The Gold Fish, Frank A. Stromsten

Proceedings of the Iowa Academy of Science

Sex differentiation in the gold fish begins in embryos of about 14 to 16 mm. in length. In the female the germ cells increase rapidly in size and have a tendency to become arranged in rows. A distinct central nucleolus is not present, but round nucleolar bodies are arranged peripherally against the nuclear membrane. These bodies seem to give off buds which pass through the nuclear membrane into the cytoplasm. During the early stages the cytoplasm becomes basophilic. In very young oocytes this is limited to a narrow zone immediately surrounding the nucleus. It then spreads peripherally until the entire …

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Notes On The Bacterial Flora Of The Snake, Roger Patrick, C. H. Werkman Jan 1930

Notes On The Bacterial Flora Of The Snake, Roger Patrick, C. H. Werkman

Proceedings of the Iowa Academy of Science

A study was made of the bacterial flora of diseased and normal snakes. The material was furnished by the Museum of the Minnesota Academy of Science, Minneapolis Public Library. Two types of disease were reported as being the cause of the death of their snakes. One, a typhoid-like disease; the other, a pneumonia. Scrapings from the intestines of the typhoid-like cases and the lungs from the snakes which had died of pneumonia were sent to this laboratory for bacteriological examination. The species from which isolations were made are as follows: Western Diamond Rattlesnake (Crotalus atrox), Timber Rattlesnake (Crotalus …

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The Effect Of Physical Factors On The Development Of Woodland And Prairie Associations In Iowa, J. M. Aikman Jan 1930

The Effect Of Physical Factors On The Development Of Woodland And Prairie Associations In Iowa, J. M. Aikman

Proceedings of the Iowa Academy of Science

The physical factors within the transition zone between the typical prairie association of the state and the deciduous forest communities occurring along the Des Moines River have been studied. The conditions for plant growth at the source of the river in northwestern Iowa have also been compared with those near the mouth of the river in southeastern Iowa. The purpose of this paper is to report the effect of the modification of factors on the distribution and grouping of woodland species and on the general reactions of the communities to the varying habitat factors.

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Decomposition Of Optically Active Diazo Compounds, Francis Earl Ray, Martha G. Hemphill Jan 1930

Decomposition Of Optically Active Diazo Compounds, Francis Earl Ray, Martha G. Hemphill

Proceedings of the Iowa Academy of Science

In 1921, Levene and Mikeska, and in 1922, Noyes and Chiles prepared optically active esters in which the only possible asymmetric carbon was that doubly bound to diazo nitrogen. Due to this double bond being semipolar the nitrogen loses an electron to the carbon. The asymmetry of the carbon atom would result from the localization of this electron much the same as the localization of the ordinary bond is considered to cause asymmetry.

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Growth, Reproduction, And Lactation On Diets Containing Soy Beans As The Sole Source Of Vitamins B And G, P. D. Wilkinson, V. E. Nelson Jan 1930

Growth, Reproduction, And Lactation On Diets Containing Soy Beans As The Sole Source Of Vitamins B And G, P. D. Wilkinson, V. E. Nelson

Proceedings of the Iowa Academy of Science

Human beings and farm animals are dependent upon seeds for a considerable portion of their food supply. Many of these substances have been the subject of rigid dietary investigations within recent years - especially the grains - because of their great economic importance. Soy beans, which have been used as a food by Chinese and Japanese for hundreds of years, are becoming of great importance in the United States. There are many varieties of soy beans known. Granthan reports the analysis of seventeen varieties, and he does not include all. The color of the bean varies from the light yellow …

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The Selection Of Thermometers For General Organic Chemistry, Thomas H. Liggett Jan 1930

The Selection Of Thermometers For General Organic Chemistry, Thomas H. Liggett

Proceedings of the Iowa Academy of Science

In selecting suitable thermometers for the use of students in General Organic Chemistry, it is often found that the ordinary chemical thermometers on the market at moderate prices have a number of defects. Some of these are as follows: 1. Graduation lines too close together, making reading difficult. 2. Lack of sufficient accuracy. 3. Stems too large, causing difficulty when more than one hole must be bored through a small cork.

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Apparatus For Determination Of Resistivity At Low Temperatures, A. G. Hoyem Jan 1930

Apparatus For Determination Of Resistivity At Low Temperatures, A. G. Hoyem

Proceedings of the Iowa Academy of Science

An apparatus has been designed following the method of Cioffi and Taylor (J. O. S. A. and R. S. T. 6, 906 (1922)), by which the resistance of 2 single crystal specimens can be determined simultaneously at temperatures ranging from liquid air to room temperature. The method is being used to investigate crystals of "spectroscopically pure" zinc.

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Polyembryony In Alfalfa And Sweet Clover, John R. Watt, J. N. Martin Jan 1930

Polyembryony In Alfalfa And Sweet Clover, John R. Watt, J. N. Martin

Proceedings of the Iowa Academy of Science

In the germination tests of alfalfa seed in the spring of 1930, one seed was discovered with two embryos. They were both normal in all structures, equal in size and behaved normally in germination. Multiple embryo sacs in the ovules of alfalfa are frequent, but it has been supposed that not more than one is able to mature and function. The presence of two embryos is evidence that two embryo sacs may mature and function.

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Progress In The Analysis Of Cosmic-Ray Observations, Leroy D. Weld Jan 1930

Progress In The Analysis Of Cosmic-Ray Observations, Leroy D. Weld

Proceedings of the Iowa Academy of Science

The report herein contained is of a preliminary character, and is intended to exhibit only the first steps of the problem in hand. At the Des Moines meeting of the American Physical Society on Dec. 31 last, the writer presented a paper in which were set forth details of a method of treating the observations of Millikan and Cameron upon the absorption of the cosmic-rays, in order to render them susceptible to adjustment by the method of least squares.

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The Earth As A Source Of Heat For Outbuildings, L. V. Crum Jan 1930

The Earth As A Source Of Heat For Outbuildings, L. V. Crum

Proceedings of the Iowa Academy of Science

The object of this experiment was to investigate the possibilities of utilizing the earth's heat near the surface to warm chicken houses, garages, and other out-buildings during extremely cold weather.

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Easternmost Foldings Of Ancestral Rockies, Charles Keyes Jan 1930

Easternmost Foldings Of Ancestral Rockies, Charles Keyes

Proceedings of the Iowa Academy of Science

Although for long it is suspected that ancestral Rocky mountains must have extended much farther to the eastward than the Front ranges of Colorado do today the actual proofs that they once did are long in forthcoming. Delay in this respect continues until oil-prospecting develops so extensively in Kansas especially. Long before these oil demonstrations the pre-Cambric crystalline basement is discovered to exist at the Missouri River much nearer to the surface than is previously thought possible. The history of this investigation is so recently given that the memoir itself may be referred to for full particulars.

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Applications Of The Strobophotograph To Phonophotography, Scott N. Reger Jan 1930

Applications Of The Strobophotograph To Phonophotography, Scott N. Reger

Proceedings of the Iowa Academy of Science

A brief description of the mechanism of the strobophotograph was given. A full description is given in the following article by Milton Metfessel: The Strobophotograph: A Device for Measuring Pitch, J. Gen. Psychol., 1929, 2, 135-139.

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