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The Influence Of Solvent On The Decomposition Of Trichloracetic Acid, J. N. Pearce, A. C. Nelson Jan 1929

The Influence Of Solvent On The Decomposition Of Trichloracetic Acid, J. N. Pearce, A. C. Nelson

Proceedings of the Iowa Academy of Science

It is a well-known fact that the rate of a given reaction is dependent upon the temperature, upon the nature and the concentration of the reactants and upon the presence of catalysts. But that which is not so well known is the mechanism by which these different factors actually influence or modify the rate of chemical change. More particularly is this true for mono-molecular reactions the number of which is known to be relatively few.

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A Spectorophotometric And Spectroscopic Study Of Phi Persei, Herbert F. Schiefer Jan 1929

A Spectorophotometric And Spectroscopic Study Of Phi Persei, Herbert F. Schiefer

Proceedings of the Iowa Academy of Science

The great importance of intensity studies in stellar spectra has long been recognized and as such has been the subject of many investigations. Most of the early studies have been on the intensity distribution of the continuous spectrum. The more recent investigations have been confined to special regions of the continuous spectrum as well as on selected spectral lines. Various methods have been used for such intensity studies.

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The Fluorescence Of Cod Liver Oil, C. A. Morehouse Jan 1929

The Fluorescence Of Cod Liver Oil, C. A. Morehouse

Proceedings of the Iowa Academy of Science

The fluorescence was produced by the radiation from a Cooper Hewitt quartz mercury vapor lamp. A Corex "A" blue purple filter was used to filter out that part of the spectrum of the exciting light in which the fluorescence appeared. The filtered light, which was almost entirely ultraviolet, was focused directly onto the surface of the cod liver oil by means of a quartz lens.

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Physical Properties Of Some Vegetables, Earl C. Mccracken Jan 1929

Physical Properties Of Some Vegetables, Earl C. Mccracken

Proceedings of the Iowa Academy of Science

Extensive investigations are being made by the Household Equipment department of the Home Economics division of Iowa State College on the possible economy of cooking foodstuffs by the direct application of an electric current. Consequently a more complete knowledge of the related physical properties of such materials is essential to the proper development of a satisfactory process. In this paper are given the results of measurements of the specific heats of some vegetables and of the internal temperatures and electrical resistances of potatoes under the action of different a.c. voltages.

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The Conductivity Of Cod Liver Oil, L. W. Butler Jan 1929

The Conductivity Of Cod Liver Oil, L. W. Butler

Proceedings of the Iowa Academy of Science

Experiments have been conducted on the conductivity of cod liver oil under different conditions. These experiments were carried out in a conductivity cell using brass plates placed in some instances about.003 inch apart and at other times at about.020 inch. The temperature of the oil was raised to approximately fifty degrees Centigrade and allowed to cool slowly to three or four degrees below zero Centigrade, readings on the conductivity being made at frequent intervals. The conductivity decreased as the temperature was lowered, the decrease becoming very rapid at the lower temperatures. When the temperature was raised, the conductivity increased, the …

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Peltier Effect In Single Crystals Of Bismuth, H. D. Fagan Jan 1929

Peltier Effect In Single Crystals Of Bismuth, H. D. Fagan

Proceedings of the Iowa Academy of Science

Some preliminary data on the Peltier Effect in bismuth single crystals have been obtained. The reference metal used is copper. The results so far obtained seem to be in fair agreement with the data computed from the thermal e.m.f. measurements of Boydston and Bridgman.

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Improved Apparatus For Growth Of Metal Crystals, A. G. Hoyem Jan 1929

Improved Apparatus For Growth Of Metal Crystals, A. G. Hoyem

Proceedings of the Iowa Academy of Science

Some preliminary data on the Peltier Effect in bismuth single crystals have been obtained. The reference metal used is copper. The results so far obtained seem to be in fair agreement with the data computed from the thermal e.m.f. measurements of Boydston and Bridgman.

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A Simple Refrigeration System For The Farm, L. V. Crum Jan 1929

A Simple Refrigeration System For The Farm, L. V. Crum

Proceedings of the Iowa Academy of Science

The object has been to find a cheap and efficient method of storing and insulating ice which might be used for cooling purposes on the farm. A large tank was filled with a solid cake of ice by adding a small amount of water each evening during cold weather. The cooling chamber consists of a small compartment directly beneath the metal base of the tank, and is well insulated from outside effects.

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X-Ray Diffraction By Organic Solutions, Alfred W. Meyer Jan 1929

X-Ray Diffraction By Organic Solutions, Alfred W. Meyer

Proceedings of the Iowa Academy of Science

Series of ionization diffraction curves of two organic solutions with varying concentrations were obtained using Mo Ka radiation. The solutions used were normal butyl alcohol with orthodimethyl-cyclohexane and normal ethyl alcohol with cyclohexane. The diffraction peaks were found to shift from the peak of one member to that of the other as the solution was changed from 100% of one member to 100% of the other. Also the width of the peak was found to vary in the same manner with the exception that the width was a maximum at a low percentage of the liquid, the peak of which …

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Molecular Structure Of Benzene, Cyclohexane And Their Derivatives - A Study In X-Ray Diffraction, G. W. Stewart Jan 1929

Molecular Structure Of Benzene, Cyclohexane And Their Derivatives - A Study In X-Ray Diffraction, G. W. Stewart

Proceedings of the Iowa Academy of Science

An examination by the x-ray diffraction ionization method was made of benzene, toluene, o-, m- and p-xylene, mesitylene, ethyl benzene and isopropyl benzene; cyclohexane, methyl cyclohexane, o-, m- and p-dimethyl cyclohexane; phenol, aniline, cyclohexanol and cyclohexanone; 2 hydroxy 1-3 dimethyl benzene and three isomers, o-, m- and p-toluidine, and o-, m- and p-cresyl methyl ether. The diffraction peaks are taken to be caused by the semi-orderly space arrangement of the molecules in the liquid, or cybotactic condition, and the distances of separation of the planes containing diffraction centers are computed by Braggs' diffraction law. Both assumptions …

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Diffraction Of X-Rays In Liquids: Effect Of Temperature, E. W. Skinner Jan 1929

Diffraction Of X-Rays In Liquids: Effect Of Temperature, E. W. Skinner

Proceedings of the Iowa Academy of Science

Using an x-ray spectrometer similar to that used by G. W. Stewart, experiments are being carried out on the effect of varying temperature on liquid scattering, temperatures varying from room temperature to near the boiling points being used. To date, two liquids, cyclohexane (27°C and 83.5°C) and heptyl (heptylic) acid (28° C and 193° C) have been examined. Results and conclusions are as follows.

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A Molecular Velocity Filter, John A. Eldridge Jan 1929

A Molecular Velocity Filter, John A. Eldridge

Proceedings of the Iowa Academy of Science

A method has previously been described by which the velocity of molecules could be measured. A qualitative combination of Maxwell's distribution law was obtained. A filter is being constructed which will have much greater resolving power and also greater sensitivity.

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Intensity Of Mercury Lines Excited By Positive Ions, C. Frische Jan 1929

Intensity Of Mercury Lines Excited By Positive Ions, C. Frische

Proceedings of the Iowa Academy of Science

Observations were made concerning the intensity of lines of the mercury spectrum as excited by positive ions. The results were compared with corresponding data on the electron spectrum given by previous observers. Intensity measurements were made with a microphotometer.

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Segmentation In Earthworms, Resulting From Inability To Regenerate A Portion Of The Ventral Nerve Cord, F. L. Fitzpatrick, S. L. Stolba Jan 1929

Segmentation In Earthworms, Resulting From Inability To Regenerate A Portion Of The Ventral Nerve Cord, F. L. Fitzpatrick, S. L. Stolba

Proceedings of the Iowa Academy of Science

The first of the two following experiments was performed in 1927-1928. Thirty-five sexually mature earthworms (Lumbricidae) were put under the influence of ether. Anesthesia was resorted to so that the subjects would remain inactive during the subsequent operation. A tiny incision was made in the ventral body wall of each specimen, at a point just posterior to the clitellum. The ventral nerve cord was then severed with a fine pointed scissors. It will be noticed that the place of operation was posterior to the more important organs of the body. It was selected as such for the foregoing reason and …

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The Address Of The President - Contributions To The Pleistocene Geology Of Iowa, George F. Kay Jan 1929

The Address Of The President - Contributions To The Pleistocene Geology Of Iowa, George F. Kay

Proceedings of the Iowa Academy of Science

Although for many years much has been spoken and written about the glacial deposits of Pleistocene age in Iowa, in connection with the meetings of this Academy and many other scientific organizations, there is as much interest in these deposits today as at any previous time. Your retiring President has chosen therefore as the subject of this address, "Contributions to the Pleistocene Geology of Iowa." It is my purpose to recall to your minds some of the geologists who have made contributions to the Pleistocene geology of Iowa, and insofar as the time at our disposal will permit to point …

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Roster And Records Of Secretary: 1903-1929, Iowa Academy Of Science Jan 1929

Roster And Records Of Secretary: 1903-1929, Iowa Academy Of Science

Iowa Academy of Science Documents

Meeting minutes, conference programs, and more from the Iowa Academy of Science during the years 1903-1929.

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What Are We Teaching In Biology?, C. W. Lantz Dec 1928

What Are We Teaching In Biology?, C. W. Lantz

Science Bulletin

This subject in order to be of real value must be an actual study of plants and animals. I have observed in my teaching that pupils, when given recognition characters of trees, may be able to pass a satisfactory examination on these characters, but fail to recognize the trees they describe when they see them in the field. They have simply memorized words that mean nothing to them.

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Stress Pertinent Facts In Health Teaching, Belva W. Swalwell Dec 1928

Stress Pertinent Facts In Health Teaching, Belva W. Swalwell

Science Bulletin

In the past, much of the health information which high school pupils acquired was handed down to them traditionally. They listened to what their elders had to say and seldom questioned the validity of it. Assertions to the effect that a buckeye carried in one's pocket would prevent rheumatism; that a piece of salt fat pork bound about the neck would counteract diphtheria; or that some malodorous substances would, if breathed, ward off certain communicable diseases were considered as truths and were passed on to the next generation. Since health is now taught in our high schools by teachers adequately …

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Highway Signs In Science Teaching, Winifred Gilbert Dec 1928

Highway Signs In Science Teaching, Winifred Gilbert

Science Bulletin

Let me assume that the General Science teachers of the state have been well prepared for their work and that at the present time they are more or less efficient teachers. Still there is the ever present task of keeping up with the curricular and learning studies that are going on in the field of General Science. New texts are appearing, yearly, new studies on content and methods seem to be on the increase and it takes rather nimble stepping on the part of the teacher to keep pace.

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Science Bulletin, Vol.1 No.2, December 1928 [Complete Issue] Dec 1928

Science Bulletin, Vol.1 No.2, December 1928 [Complete Issue]

Science Bulletin

A Service Bulletin for Teachers of High School Science.

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A Correspondent Reminds Us . . . Dec 1928

A Correspondent Reminds Us . . .

Science Bulletin

A correspondent reminds us that some teachers of science leave the impression in the class that our present knowledge of science was given to the world ready made or grew out of the presses that printed the text.

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Editorially Speaking Dec 1928

Editorially Speaking

Science Bulletin

We greatly appreciate the friendly comments on the first issue of the SCIENCE BULLETIN from our readers; and we have tried to answer your questions. In these first issues we are of necessity "feeling our way in the dark". You only, friendly reader, can give us light.

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Laboratory Equipment And Experiments For Determinations Of Density, L. Begeman Dec 1928

Laboratory Equipment And Experiments For Determinations Of Density, L. Begeman

Science Bulletin

Laboratory experiments in Density require the following apparatus: beam balances, meter sticks, graduates, calipers, tumblers, test tubes, and hydrometers. There should be as many of each as possible· in order to reduce the amount of group work. The objects for study should include pieces of lead, zinc, marble, paraffin, beeswax, glass stoppers, shot, gasoline and solutions of salts such as blue vitriol.

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Hydrostatics, L. Begeman Dec 1928

Hydrostatics, L. Begeman

Science Bulletin

The teacher may introduce this subject to the class by reference to the meaning of "pressure" as used in mechanics. Explain to them that the gauge pressure in a steam boiler or auto tire refers to the number of pounds pressure on each square inch of inner surface. Sometimes a problem will make it clear.

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Something From Nothing, W. H. Kadesch Dec 1928

Something From Nothing, W. H. Kadesch

Science Bulletin

Matter made while you wait-hydrogen, helium, oxygen, iron or what will you have? No, it has not quite come to this! But the time-honored law of conservation which states that matter is neither destructible nor creatable is no longer accepted as unquestionably and universally true.

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Laboratory Upkeep, R. W. Getchell Dec 1928

Laboratory Upkeep, R. W. Getchell

Science Bulletin

Proper care of the laboratory is the phase of the high' school chemistry teacher's task most apt to be neglected. This and later articles will point out some of the " little things that make perfection."

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Fall And Winter Material In Animal Husbandry, H. Earl Rath Dec 1928

Fall And Winter Material In Animal Husbandry, H. Earl Rath

Science Bulletin

Swine are now going to market in large numbers. This offers an excellent opportunity to study market types as represented in the herd and compare them with the sows from which they were produced. If brood sows for spring litters have not all been selected, the teacher has some valuable work for pupils in selecting the better prospects from the available groups.

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Title - Masthead Dec 1928

Title - Masthead

Science Bulletin

A Service Bulletin for Teachers of High School Science.

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Introducing Ourselves Nov 1928

Introducing Ourselves

Science Bulletin

With this issue of the Science Bulletin, the Iowa State Teachers College enters upon a definite program of class-room service to the teachers of high school sciences of the state. This big family of fifteen hundred science teachers arc handling a b ranch of instruction which is unsurpassed, not only in its fascination but in its rapid development and change in teaching methods and subject matter. You, fellow science teacher, as a member of our great state educational system, are entitled to all of the assistance which this state supported Teachers College can offer you.

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Some Suggestions For Winter Study Of Biology In High Schools, Roy L. Abbott Nov 1928

Some Suggestions For Winter Study Of Biology In High Schools, Roy L. Abbott

Science Bulletin

Considerable criticism has recently been directed against the commonly accepted methods of teaching Biology in our secondary school and colleges. John Burroughs once re- marked that he had never dissected an animal and was glad of it, implying by this, I take it, that we do not learn Nature by dissecting her children. Recently Wheeler of Harvard, has voiced a similar criticism by saying that our teaching of Biology is suffering from academic dry rot; that laboratory dissection of a dead animal gives the student a knowledge of the details of structure of that animal without giving any knowledge of, …

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