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Further Species Crosses In The Genus Cucurbita, Edward F. Castetter Jan 1926

Further Species Crosses In The Genus Cucurbita, Edward F. Castetter

Proceedings of the Iowa Academy of Science

During the past few years attempts have been made to cross the three cultivated species of the genus Cucurbita. There was used in Cucurbita maxima a pure line of Hubbard squash, known as the "Kitchenette"; in Cucurbita Pepo a pure line of the Connecticut Field pumpkin, and in Cucurbita moschata a pure line of the Large Cheese pumpkin.

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Paired Ovules Of Vallisneria, Robert B. Wylie Jan 1926

Paired Ovules Of Vallisneria, Robert B. Wylie

Proceedings of the Iowa Academy of Science

In studying Vallisneria spiralis abnormal ovules were often noted. The most frequent abnormality is the occurrence of symmetrical double or paired ovules. Upon a common funiculus are borne two nucelli each possessing an inner integument, the whole enclosed by a single outer integument (Figs. 1, 2, 3). Malformations occur rarely and most of them are sterile. In Fig. 7 is shown an ovule having normal integuments with some suggestion of doubling in the nucellus but with plain dominance by the functional or larger part.

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Systematic Botany, B. Shimek Jan 1926

Systematic Botany, B. Shimek

Proceedings of the Iowa Academy of Science

When some years ago the reaction against the "old botany" and in favor of plant morphology, and later plant physiology, took place, systematic botany was pushed into the back-ground, indeed in many of our institutions it was barred entirely.

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The Transference Numbers And The Degree Of Solvation Of The Ions Of Lithium Chloride In Certain Alcohols, J. N. Pearce, W. G. Eversole Jan 1926

The Transference Numbers And The Degree Of Solvation Of The Ions Of Lithium Chloride In Certain Alcohols, J. N. Pearce, W. G. Eversole

Proceedings of the Iowa Academy of Science

The low migration velocities of some of the ions of the elements of low atomic weight, as well as the many other phenomena that are not explained by simple electrolytic dissociation, have led to the belief that the ion does not lead an independent existence in the solution, but is solvated, or combined chemically with one or more molecules of the solvent.

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The Effect Of The Addition Of Sodium Carbonate And Sodium Silicate On The Casting Properties Of Clay Slip, F. E. Brown, Chi-Fang Lai Jan 1926

The Effect Of The Addition Of Sodium Carbonate And Sodium Silicate On The Casting Properties Of Clay Slip, F. E. Brown, Chi-Fang Lai

Proceedings of the Iowa Academy of Science

The addition of small amounts of Na2CO3, or of Na2Sio3 increases the plasticity of some clay slips and permits them to be cast when they contain a much smaller percentage of water. This permits a much more rapid casting. Casts were made and removed from the mould in 20 minutes. The time for a cast increased for successive casts as the mould became filled with water. After drying the original rate was possible. A mixture of Na2CO3 and Na2Sio3 was found to be superior to either alone. …

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A Continuous Reading Electro-Titration Apparatus, Stephen Popoff, J. Hildebrand Jan 1926

A Continuous Reading Electro-Titration Apparatus, Stephen Popoff, J. Hildebrand

Proceedings of the Iowa Academy of Science

Goode's Single radio tube electro-titration set up was modified so as to give greater sensitivity. In place of the galvanometer a microammeter reading to 750 microamperes is used in the circuit.

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The Utilization Of Cob Char As A Carburizing Agent, H. L. Maxwell Jan 1926

The Utilization Of Cob Char As A Carburizing Agent, H. L. Maxwell

Proceedings of the Iowa Academy of Science

It is shown that the char resulting from the distillation of corn cobs in the manufacture of furfural, may be substituted for the more expensive bone char now being used in the carburizing process. The distribution of the tri-ferro carbide, Fe3C, in the carburized zone may be closely governed by time and temperature variations.

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New Derivatives Of Vanillin, G. Carroll Hilman, O. H. Alderks Jan 1926

New Derivatives Of Vanillin, G. Carroll Hilman, O. H. Alderks

Proceedings of the Iowa Academy of Science

Monobromovanillin was prepared by Carles (Bull. Soc. Chim., 17, 12 (1872) and further investigated by Tiemann and Haarman (Ber., 7, 615 (1874). More recently, Brady and Dunn CJ. Chem. Soc., 107, 1859 (1915) studied the corresponding oxime, which was found to exist in but one of the stereoisomeric forms required by the theory. In the present work a dibromo derivative of vanillin, which has not hitherto been reported, has been prepared by a method that gives a high yield. Among its derivatives it has been found that the oxime exists in but one form, and that the nitril obtained from …

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Action Of Potassium Carbonate On Certain Phenyl Alkyl Ethers, L. Chas. Raiford, D. M. Birosel Jan 1926

Action Of Potassium Carbonate On Certain Phenyl Alkyl Ethers, L. Chas. Raiford, D. M. Birosel

Proceedings of the Iowa Academy of Science

When a ligroin solution of phenyl isopropyl, isobutyl or isoamyl ether was shaken with dry potassium carbonate, we obtained crystalline products that were readily soluble in water to give alkaline liquids. When dilute acid was used, the corresponding ether was set free. The analyses of these products indicated that one atomic weight of potassium is combined with two molecular proportions of ether. So far, no such combinations have been obtained with the carbonates of lithium and sodium. Tests will be made with rubidium and caesium carbonates later

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Butler's Landing Outlier And Its Fossil Flora, John E. Adams Jan 1926

Butler's Landing Outlier And Its Fossil Flora, John E. Adams

Proceedings of the Iowa Academy of Science

The early geologists who surveyed the state reported many small, scattered patches of Pennsylvanian sandstone north and east of the principal Pennsylvanian area in Iowa, The outliers along the Iowa River north and east of Iowa City were among the first to be described. Subsequently more complete descriptions of these and other outliers in Johnson and adjacent counties have appeared in the publications of the Iowa Geological Survey and in other scientific journals. References to these articles can be found in Ia. Geol. Survey Rept. Vol. 22, 1912.

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The Bone Deposit At Cherokee, E. J. Cable Jan 1926

The Bone Deposit At Cherokee, E. J. Cable

Proceedings of the Iowa Academy of Science

Last fall while the writer was classifying material for the Cherokee high school museum, Mr. N. Stiles, one of the leading citizens of the town who is interested in geology and history, and who has made an excellent collection of Indian, geological and historical material for the high school museum, suggested to the writer that he thought he knew where there might be a deposit of fossil bones. The writer became interested immediately and accompanied Mr. Stiles to the place in question. After a careful examination it was found that the bones represent a rich deposit of mammalian remains.

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Some Observations On Undertow, A. L. Lugn Jan 1926

Some Observations On Undertow, A. L. Lugn

Proceedings of the Iowa Academy of Science

Undertow has been the subject of considerable discussion among geologists and has received some attention in the press. Some hold that it is a continuous return flow of water along the bottom from a shoreline and others contend that it is a pulsatory return of water alternating with its piling up due to the shoreward movement of waves of translation.

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Some Recent Finds Of Remains Of The Extinct Ground Sloth In Southwest Iowa, Fred Delavan Jan 1926

Some Recent Finds Of Remains Of The Extinct Ground Sloth In Southwest Iowa, Fred Delavan

Proceedings of the Iowa Academy of Science

Evidence of the extinct ground sloth in Iowa is very meager, but additional remains are being brought forth yearly. At the present time the knowledge of its presence is limited almost entirely to the counties bordering the Missouri River; the one exception is Dubuque County, in the middle-eastern portion of the state. Three specimens have been added to the collection in the past year. A tooth of the Megalonyx from Dixon Creek, Fremont County, collected by George Day, and a tooth and claw bone from Chabaneau Creek, Mills County, collected by the writer. The tooth from Chabaneau is exceptionally long …

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A Horntail Trilobite From Mcgregor, Iowa, A. O. Thomas Jan 1926

A Horntail Trilobite From Mcgregor, Iowa, A. O. Thomas

Proceedings of the Iowa Academy of Science

Recently an excellent specimen of the horntail trilobite was collected at McGregor by Miss Florence S. Chapin a member of the geology field class of the McGregor Wild Life School. This fossil is so rarely found in other than fragmentary condition in Iowa that any well-preserved specimen deserves to be recorded and illustrated. The specimen presents the dorsal shield, is unrolled, and retains the head, thorax and pygidiurn or tail shield. The right margin of the head, the right free cheek and the tips of the tail spines are missing. When found only a part of the axial lobe and …

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The Use Of Cone-In-Cone Structure For The Purpose Of Correlation, A. C. Tester Jan 1926

The Use Of Cone-In-Cone Structure For The Purpose Of Correlation, A. C. Tester

Proceedings of the Iowa Academy of Science

Recently the writer published, in conjunction with Dr. W. H. Twenhofel, a short paper concerning certain Comanchean strata of Central Kansas. Because of the northern extension of these beds beyond the Kansas boundary it seems desirable to explain one of the criteria used in tracing the beds northward.

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Taxonomy Of Iowa's Glacial Deposits, Charles Keyes Jan 1926

Taxonomy Of Iowa's Glacial Deposits, Charles Keyes

Proceedings of the Iowa Academy of Science

From the angle of genesis we lately have to modify some of our ideas on our Glacial till-sheets. Realizing that the continental ice-masses do not emanate from a single center, it is found that our Iowa tills come from what is known as the Keewatin center, on the west of Hudson Bay; while the tills on the east side of the Mississippi River originated mainly from the Labradoran center. The only invasion of ice from the last mentioned center is a slight one by the Illinoian ice, in the extreme southeastern part of our state.

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Notes On The Progress Of The Physiographic Evolution Of Lake Cooper, Ben H. Wilson Jan 1926

Notes On The Progress Of The Physiographic Evolution Of Lake Cooper, Ben H. Wilson

Proceedings of the Iowa Academy of Science

1. Lakes possess life histories which develop along orderly lines. 2. This fact holds true for artificial lakes as well as for those formed in the processes of natural earth history. 3. A historic, geographic and physiographic description of Lake Cooper. 4. A brief statement of those processes which are involved in the orderly evolution of Lake Cooper. 5. A brief examination into the present state and stage of these processes.

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The Occurrence Of The Brachiopod Bilobites Bilobus In The Silurian Of Iowa, A. O. Thomas Jan 1926

The Occurrence Of The Brachiopod Bilobites Bilobus In The Silurian Of Iowa, A. O. Thomas

Proceedings of the Iowa Academy of Science

The small brachiopod, Bilobites bilobus, was first described by Linnaeus in the 12th edition of his Systema Naturae in 1767. Though frequently reported since then from several Silurian horizons in both Europe and America this is the first occurrence in the Silurian of Iowa.

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Proboscidian Remains From Red Oak And Ottumwa, Iowa, A. O. Thomas Jan 1926

Proboscidian Remains From Red Oak And Ottumwa, Iowa, A. O. Thomas

Proceedings of the Iowa Academy of Science

During the past year several very interesting proboscidian bones have been found in the Pleistocene deposits of Iowa. The first of these is the skull of a mastodon unearthed at some depth in an excavation near Red Oak. The mandible and tusks are lacking and the brain case has been broken away posteriorly. The face is well preserved and shows clearly the sutures, the various foramina, the anterior nares, the high forehead, and the great alveoli for the massive tusks. A well preserved molar is in place in each half jaw. The damaged condition posteriorly reveals unusually well the cancellated …

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Relativistic Reflections, Edward S. Allen Jan 1926

Relativistic Reflections, Edward S. Allen

Proceedings of the Iowa Academy of Science

An important result of the great interest in the theory of relativity has been that mathematicians and physicists on the one hand, philosophers on the other, have given increasing attention to each other's work. It may not, then, be out of place for one whose interest in the subject has been mainly on the mathematical side to examine some philosophical inferences which have been drawn from it.

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Further Evidence Of The Effect Of Valence And Chemical Combination On The K Limit Of Sulphur, R. A. Rogers Jan 1926

Further Evidence Of The Effect Of Valence And Chemical Combination On The K Limit Of Sulphur, R. A. Rogers

Proceedings of the Iowa Academy of Science

A number of spectrograms have been obtained showing the K absorption limit of sulphur. The absorption was due to sulphur in the gypsum (Ca SO4. 2H2O) crystal used in the analysis of the M series absorption spectra of the platinum group.

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A New Type Of Photoelectric Colorimeter, D. H. Palmer, Jay W. Woodrow Jan 1926

A New Type Of Photoelectric Colorimeter, D. H. Palmer, Jay W. Woodrow

Proceedings of the Iowa Academy of Science

A photoelectric colorimeter has been constructed which is capable of detecting small changes in the color of meat. With this apparatus it was possible to measure the variation in the color of meat as a function of the time of exposure to the air. The effects of temperature upon the color variation were also measured; and some data has been obtained showing the relation between the color and the grade of the meat.

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Effects Of Irradiated Oils On Photographic Films, Jay W. Woodrow, A. C. Bailey Jan 1926

Effects Of Irradiated Oils On Photographic Films, Jay W. Woodrow, A. C. Bailey

Proceedings of the Iowa Academy of Science

During the past two years, there has been considerable discussion on the question of the emission of ultra-violet light by cod liver oil. Our experiments have confirmed the opinion that no radiations are emitted which can penetrate plates of fused quartz one millimeter in thickness. However, an image is produced on a photographic film placed directly above the oil, an effect which is attributed to a direct chemical action. We have also found that other oils which would not produce images on the photographic film can be activated by ultra-violet light so that they act like cod liver oil. Different …

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The Moulding Action Of Surface Tension On A Free Sheet Of Water, L. B. Spinney Jan 1926

The Moulding Action Of Surface Tension On A Free Sheet Of Water, L. B. Spinney

Proceedings of the Iowa Academy of Science

A smooth stream of water falling vertically is allowed to strike the center of a small circular plate placed horizontally. The water under these circumstances spreads laterally over the edge of the plate in a thin stream. Under the action of gravity and surface tension this thin bubble-like stream assumes various forms determined by the velocity of the stream impinging upon the plate and the dimensions of the various parts of the apparatus. The bubble may be made to assume a more or less nearly spherical form or, by joining a free water surface below, to shape itself into the …

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The Toxic Effect Of Ultra Violet Radiations Upon Yeast And Yeast-Growing Media, A. C. Bailey Jan 1926

The Toxic Effect Of Ultra Violet Radiations Upon Yeast And Yeast-Growing Media, A. C. Bailey

Proceedings of the Iowa Academy of Science

We have not found in our work any region of ultra violet energy which will produce a stimulation of yeast growth in any synthetic medium used. In every case the action of the ultra violet radiations has produced a toxicity in the media in proportion to the amount of ultra violet received. Even fifteen minutes of ultra violet light at 16 cm. from the lamp produced such a toxicity in the medium that the yeast count twenty-four hours afterwards was ten per cent below the control count.

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A Vacuum Tube Tester For Routine Work Using Alternating Current, P. S. Helmick Jan 1926

A Vacuum Tube Tester For Routine Work Using Alternating Current, P. S. Helmick

Proceedings of the Iowa Academy of Science

Some form of vacuum tube tester is a necessity in every radio laboratory. The vacuum tube tester herewith described is the result of an effort to design a simple instrument suitable for routine work, and which could be left permanently connected to the lighting circuit thus being always ready for use.

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Magnetic Properties Of Thin Films Of Iron, Electrolytically Deposited, E. P. T. Tyndall Jan 1926

Magnetic Properties Of Thin Films Of Iron, Electrolytically Deposited, E. P. T. Tyndall

Proceedings of the Iowa Academy of Science

Films of iron from 100 to 200 millimicrons thick deposited electrolytically from neutral and acid solutions of iron ammonium sulphate show a surprising magnetic hardness. At a field of 40 gauss the intensity of magnetization is from 200 to 300 c.g.s. units. No sudden increase in magnetization is found up to fields of 150 gauss. Films deposited on the initial film, using much smaller current densities than that required for the initial deposit, show the usual properties of electrolytic iron. An intensity of magnetization of 1000 is reached at 40 gauss field. The cause of the hardness of the initia1 …

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Potentials Of Spark Lines Of Mercury Vapor, J. A. Eldridge Jan 1926

Potentials Of Spark Lines Of Mercury Vapor, J. A. Eldridge

Proceedings of the Iowa Academy of Science

It has been shown by a series of photometric readings on thirty spark lines of mercury falling in the range 2000-5000 angstroms, that these lines fall into three groups. (1) Excitation potential at about 20 volts, (2) excitation potential about 28 volts and (3) excitation potential about 55 volts. The exact values of these potentials are uncertain since they depend upon pressure and current conditions. If we accept the results of Smythe that double ionization occurs first at 20 volts and triple ionization certainly not under 100 volts we may suppose the first class of lines as due to the …

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A Comparison Of Power Output Conical, Hyperbolic And Exponential Trumpets, G. W. Stewart Jan 1926

A Comparison Of Power Output Conical, Hyperbolic And Exponential Trumpets, G. W. Stewart

Proceedings of the Iowa Academy of Science

These measurements are presented as illustrative of the advances that have been made in the measurement of acoustic power. They refer of course to single cases, but they are of interest in showing the actual fluctuations of both components of impedance and of the power output in the three types of trumpets stated in the title.

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Direct Absolute Measurement Of Acoustic Impedance, G. W. Stewart Jan 1926

Direct Absolute Measurement Of Acoustic Impedance, G. W. Stewart

Proceedings of the Iowa Academy of Science

Advantage is taken of the author's theory of the transmission in an acoustic line with an attached branch which alters the intensity and the pressure phase of the transmitted sound. By the measurement of the relative intensities and phases with and without the branch present, it is possible to obtain the components Z1 and Z2 of the impedance, Z = Z1 + iZ2 , of the branch.

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