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The Organization Of An Academy, Joseph C, Gilman
The Organization Of An Academy, Joseph C, Gilman
Proceedings of the Iowa Academy of Science
The Academy Conference of the American Association for the Advancement of Science is the one place in which representatives of the state academies meet for discussion of their common interests and problems. Since in the past ten years other immediate needs have held its attention, no discussion of the ever present problem of the methods of attaining its objectives has been presented, hence the present subject: - the organization of an academy-was chosen for discussion. As qualifications for presenting this material, the experiences during the past ten years as secretary of the Iowa Academy of Science and also the representative …
The Address Of The President: Science And Progress, R. B. Mcclenon
The Address Of The President: Science And Progress, R. B. Mcclenon
Proceedings of the Iowa Academy of Science
Science and human welfare have always risen and fallen together. We find this generalization borne out in all recorded history, and even farther back in the dim horizons of prehistory. From the first attempts at counting and measuring, observation of the precision of the periodic recurrence of the seasons, forging of metal tools and weapons, domestication of animals, planting and harvesting of crops, we see that the slow advance of the status of man in his world has been accompanied or even preceded by the advance in science. In the earlier stages, of course, we find art, culture, and the …
The Rose Crimson Rambler And Its Progenies, Clark D. Paris, T. J. Maney
The Rose Crimson Rambler And Its Progenies, Clark D. Paris, T. J. Maney
Proceedings of the Iowa Academy of Science
The year 1893 is an important landmark to the rosarian as in that year Charles Turner of Slough, England, introduced the Crimson Rambler rose to the occidental world. Nothing is known of its parentage, it having been introduced from Japan where it had been grown for an unknown period of time. When it was first introduced it was called the "Engineer." Later, it was known as "Turner's Crimson Rambler." Still later the name Turner was dropped, making it the "Crimson Rambler" as we know it today. Without regard to name, this rose introduction has proven to be a prolific parent …
Thirty Iowa Liverworts, Henry S. Conard
Thirty Iowa Liverworts, Henry S. Conard
Proceedings of the Iowa Academy of Science
Two years ago a distribution of "One Hundred Iowa Mosses" (Conard, 1939) was reported to the Academy. Vie are now about to send out "Thirty Iowa Liverworts." 10. University of Michigan, Ann Arbor, Mich. In general liverworts are much scarcer in a prarie region than mosses. There is no possibility of ever distributing another thirty species. Most of the liverworts of Iowa are woodland plants: plants of mesic habitat, in complete or partial shade (Plagiochila, Lophocolea, Frullania, Porella). Some occur on moist shaded sandstone - our most mesic condition (Plectocolea, Leiocolea, Jamesoniella, Jungermannia. Conard 1940). Anthoceros must be considered hydric. …
Flower Bud Development In Some Varieties Of Tulip, John E. Sass
Flower Bud Development In Some Varieties Of Tulip, John E. Sass
Proceedings of the Iowa Academy of Science
A study is being made of the time of initiation and development of the flower bud in three classes of tulips. All floral organs are present in November. The flower bud is twice as large in the earliest (Mendel) class than in the latest (Darwin) class, but the cytological condition in the anthers and ovules is strikingly similar; pollen is in the late quartet to early microspore stage, ovules are very small primordia with no evidence of integuments or megaporocyte. Expansion of flower bud size is in proportion to earliness, pollen development is virtually parallel, and megagamentophyte development is slightly …
A "Twin-Embryo" Abnormality In Maize, John E. Sass, George F. Sprague
A "Twin-Embryo" Abnormality In Maize, John E. Sass, George F. Sprague
Proceedings of the Iowa Academy of Science
A mutant strain of corn obtained by ultra violet treatment has twin growing points in the embryo. The flattened emerging coleoptile is a continuous sheath, containing two distinct stem apices, each of which lays down a series of leaf primordia. Each growing point becomes encircled by its laterally overlapping young leaves. The procambium strands of the two young axes converge into the stele of the mesocotyl (first internode), which is common to the two potential stems.
Temperature And Photoperiod In Relation To Flowering In Cucumis Sativus, Loran L. Danielson
Temperature And Photoperiod In Relation To Flowering In Cucumis Sativus, Loran L. Danielson
Proceedings of the Iowa Academy of Science
Cucumber plants grown under long-day and exposed to low night temperature showed a decided modification of the flowering response usually obtained under long-day conditions.
The Effect Of Riboflavin On The Growth Of Plants, Raymond Dennison
The Effect Of Riboflavin On The Growth Of Plants, Raymond Dennison
Proceedings of the Iowa Academy of Science
No abstract provided.
The Semi-Micro Adaption Of The Iowa System Of Qualitative Analysis, Lothrop Smith, Reuben E. Peterson
The Semi-Micro Adaption Of The Iowa System Of Qualitative Analysis, Lothrop Smith, Reuben E. Peterson
Proceedings of the Iowa Academy of Science
During the last few years much effort has been expended in attempts to develop apparatus and special techniques for the analysis of small quantities of material. These procedures can be divided into two classes, the micro and the semi-micro. Micro analysis deals with samples up to or about 3-5 milligrams. This micro method consumes much less time, requires smaller quantities of reagents, requires much less of the unknown and in other ways proves superior to macro analysis. However, strict micro analysis often requires the use of a microscope and other delicate pieces of apparatus, as well as a knowledge of …
How Much Time For The General Chemistry Laboratory?, Edwin O. Price
How Much Time For The General Chemistry Laboratory?, Edwin O. Price
Proceedings of the Iowa Academy of Science
The method of teaching science in which a certain amount of opportunity is given each student for work by himself in the laboratory (the so-called individual laboratory method) is of fairly recent development. Many of the early American professors of chemistry did not believe that the beginning student should be allowed to set foot in a laboratory. This was undoubtedly due to the fact that these instructors were educated under the German system of class-room demonstration. According to Lucasse (1) the credit for the development of the first chemistry laboratory for instruction goes to Lomonossoff (1748). Later the passage of …
Semi-Micro Analysis Of Tungsten, Jack Hinman, W. C. Oelke
Semi-Micro Analysis Of Tungsten, Jack Hinman, W. C. Oelke
Proceedings of the Iowa Academy of Science
The growing use of tungsten in high speed steels and for electrical purposes makes it increasingly desirable to include this element in the scheme of analysis. Metallic tungsten is seldom if ever found in nature, but occurs in several well-crystallized tungsten minerals of which Scheelite, CaW04 , is typical. From its position in the periodic table, Group VI - Series 6, one should expect tungsten to have amphoteric properties. Although we are more familiar with tungsten in the metallic state, it almost invariably behaves as a non-metal in chemical combination. For this reason in analytical work tungsten naturally falls …
The Equilibrium Between Gelatin And Water Vapor At 25° C, W. G. Eversole, Fred Fordemwalt
The Equilibrium Between Gelatin And Water Vapor At 25° C, W. G. Eversole, Fred Fordemwalt
Proceedings of the Iowa Academy of Science
The equilibrium between gelatin and water vapor from 0 per cent to 100 per cent saturation has been measured by weighing the gelatin after suspending it in the vapor to constant weight. The gelatin sample was suspended on a calibrated quartz spring and placed in a closed apparatus with an aqueous solution of known vapor pressure. The rate of attainment of equilibrium was greatly increased by pumping the air from the system. The isotherms have been determined at 25 ° for untreated isoelectric gelatin, gelatin treated with thallous thiocyanate, and gelatin treated with thallous sulfate.
The Diffusion Coefficient Of Cupric Sulfate At 25°, W. G. Eversole, J. D. Peterson
The Diffusion Coefficient Of Cupric Sulfate At 25°, W. G. Eversole, J. D. Peterson
Proceedings of the Iowa Academy of Science
The diffusion of cupric sulfate into water has been studied by measuring the concentration at different distances and at successive times as the diffusion progressed. The cupric sulfate was allowed to diffuse upward from a solution of constant concentration into a thin flat cell of optical glass filled with pure water. The concentration at different distances from the open end of the cell, was determined by measuring the absorption of monochromatic red light. The diffusion coefficient has been calculated by using a method similar to Zuber's for the integration of the general form of the equation for linear diffusion in …
Preparation Of Tyrosine From Steffen's Waste, Edward Bartow, Harland L. Wetzstein
Preparation Of Tyrosine From Steffen's Waste, Edward Bartow, Harland L. Wetzstein
Proceedings of the Iowa Academy of Science
In the search for substances, other than glutamic acid, betaine, and potassium chloride that might be obtained from Steffens waste, a quantity of concentrated waste, sp. gr. 1.4, was diluted with an equal volume of water, boiled with a small amount of activated carbon, and filtered. A precipitate which formed on cooling was identified as I-tyrosine. Though it had been found in beet molasses, it is apparently the first time that tyrosine has been obtained from Steffen's waste. In 1846, Justus von Liebig discovered tyrosine in cheese (3). Since then it has been found in many substances containing proteins. v. …
Vapor Density, Liquid Density And Surface Tension Of Solutions Of Potassium Thiocyanate In Liquid Sulfur Dioxide For 10° To 25° C, W. G. Eversole, G. H. Wagner
Vapor Density, Liquid Density And Surface Tension Of Solutions Of Potassium Thiocyanate In Liquid Sulfur Dioxide For 10° To 25° C, W. G. Eversole, G. H. Wagner
Proceedings of the Iowa Academy of Science
The vapor density, liquid density and differential capillary rise of pure liquid sulfur dioxide, and sulfur dioxide solutions of potassium thiocyanate were measured at 10, 15, 20, and 25°C in a sealed apparatus which allowed the measurement of all these quantities on the same solution. The apparatus consisted of two Pyrex capillaries sealed on to a Pyrex tube of 16.3 mm diameter in which a quartz bob was suspended from a calibrated quartz spring. By weighing the bob in the vapor, inverting, and weighing in the liquid, the densities could be determined to ± 0.02 mg/ml. All distances including the …
The Production Of Chloropicrin As Needed From Dry Mixtures Of Picric Acid And Bleaching Powder, O. R. Sweeney, L. K. Arnold, R. K. Dix, W. R. Stelzer Jr.
The Production Of Chloropicrin As Needed From Dry Mixtures Of Picric Acid And Bleaching Powder, O. R. Sweeney, L. K. Arnold, R. K. Dix, W. R. Stelzer Jr.
Proceedings of the Iowa Academy of Science
Chloropicrin or trichloromethane is a colorless liquid boiling at l 12°C and having a specific gravity of 1.69. It was first prepared by Stenhouse from picric acid and bleaching powder. Its first use was in chemical warfare by the Allied troops in 1918. It was prepared in large quantities at Edgewood Arsenal during the World War, by the method developed and patented by the senior author. Picric acid, hydrated lime, and water were mixed to form a calcium picrate suspension. This suspension together with a suspension of bleaching powder and water was run into a still. The chloropicrin was steam-distilled …
Estimation Of The Composition Of Three Component Liquid Mixtures, S. G. Measamer, O. R. Sweeney
Estimation Of The Composition Of Three Component Liquid Mixtures, S. G. Measamer, O. R. Sweeney
Proceedings of the Iowa Academy of Science
While carrying out research on the extraction of oil from soybeans using mixtures of various solvents, it was quite often necessary to know the composition of a mixture of liquids containing three components. A search of the literature for ways of obtaining the composition of such mixtures by the use of physical constants revealed a very convenient method employing a combination of density and refractive index. Before this method can be used, however, solutions covering the entire ternary system must be made up accurately, their refractive indices and densities taken and plotted in such a manner that the composition of …
Ammonia And Organic Nitrogen Determinations In Stream Pollutions Studies, Jack J. Hinman Jr., W. Keith Weeber, R. Rupert Kountz
Ammonia And Organic Nitrogen Determinations In Stream Pollutions Studies, Jack J. Hinman Jr., W. Keith Weeber, R. Rupert Kountz
Proceedings of the Iowa Academy of Science
Determinations of ammonia in water supplies go back to the time of Chevreul in 1811. Titration procedures for the estimation of the substance were worked out by Boussingault (2), Bineau (1) and Thompson (9) during the 18SO's. And there are already numerous modifications of the method for the estimation of total organic nitrogen developed by Johann Kjelclahl (6) in the Carlsberg Laboratory, in Copenhagen, in 1883. It is not meant to imply, by the title given this paper that basically new and original methods for the determination of nitrogen as ammonia or in its organic compounds are to be presented. …
Oxidation Of 4-Acyloxy Derivatives Of Cinnamic Acid, Victor S. Webster, L. Chas. Raiford
Oxidation Of 4-Acyloxy Derivatives Of Cinnamic Acid, Victor S. Webster, L. Chas. Raiford
Proceedings of the Iowa Academy of Science
It is known that benzaldehyde (17) and its alkyl, alkoxy and halogen substitution products are easily oxidized to the corresponding acids. In many cases contact with air brings about the change (4). The presence of hydroxyl as a substituent often makes the aldehyde less reactive toward oxidizing agents. For example, Bücking (3) and Fitting and Remsen (5) reported that p-hydroxybenzaldehyde and protocatechuic aldehyde, respectively, are not readily oxidized by potassium permanganate solution, but require fusion with caustic potash to give the related acids. Tiemann (13) found that when vanillin, the 3-methyl ether of protocateuchuic aldehyde, is treated with oxidizing agents …
Pyrolidines From Primary Amines, George H. Coleman, Chris C. Schulze, Harold A. Hoppens
Pyrolidines From Primary Amines, George H. Coleman, Chris C. Schulze, Harold A. Hoppens
Proceedings of the Iowa Academy of Science
Pyrrolidine has been prepared from n-butylamine by heating N-chloro-N-acyl derivatives of the amine with concentrated sulfuric acid. N -chloro-N-butylacetamide underwent ring closure with the formation of pyrrolidine in SO per cent yields when heated with 95 per cent sulfuric acid for one hour at 130-140°. With 99.5 per cent acid the percentage yield was much lower. N-chloro-N-n-butyl-p-toluenesulfonamide when heated with 95 per cent sulfuric acid for thirty minutes at 140° formed pyrrolidine in 50 per cent yields. In both cases considerable amounts of n-butylamine were also formed.
Direct Syntheses Of Amides From Long-Chained Aliphatic Amines, Byron A. Hunter, William I. Harber, H. Gilman
Direct Syntheses Of Amides From Long-Chained Aliphatic Amines, Byron A. Hunter, William I. Harber, H. Gilman
Proceedings of the Iowa Academy of Science
An examination has been made of direct procedures for the synthesis of amides. Dodecylamine, tetradecylamine, hexadecylamine and octadecylamine have been treated with a variety of aliphatic and aromatic acids. Direct heating of the amine and acid, in open containers and at elevated temperatures, gave quite satisfactory yields of amides. This direct procedure has been resolved into two stages. First, a mixture of amine and acid, dissolved or suspended in warm petroleum ether, gives promptly and in good yield the corresponding salt. These salts can be used for the characterization of amine and acid. Second, when the salts are heated they …
Permian Ammonoids From Southernmost Mexico, A. K. Miller, W. M. Furnish
Permian Ammonoids From Southernmost Mexico, A. K. Miller, W. M. Furnish
Proceedings of the Iowa Academy of Science
Representatives of the ammonoid genera Perrinites and Peritrochia are described from south of Chiocomuselo, Chiapas. It is concluded that the containing beds belong in the Leonard series.
Permian Ammonoids From Greenland, A. K. Miller, W. M. Furnish
Permian Ammonoids From Greenland, A. K. Miller, W. M. Furnish
Proceedings of the Iowa Academy of Science
Danish expeditions under the leadership of Lauge Koch have collected several ammonoids from the "Martinia beds" of Clavering Island, northeastern Greenland. The genus Cyclolobus, which is well represented, indicates that the fauna is younger than any other Paleozoic ammonoids known from the Western Hemisphere. The containing beds are assigned to the uppermost Permian and correlated with the upper Products limestone of the Salt Range in India.
The Microfossils In A Pre-Kansan Peat Deposit Near Belle Plaine, Iowa, L. R. Wilson, R. M. Kosanke
The Microfossils In A Pre-Kansan Peat Deposit Near Belle Plaine, Iowa, L. R. Wilson, R. M. Kosanke
Proceedings of the Iowa Academy of Science
In 1937 a portion of U. S. Highway 30 near Belle Plaine, Iowa was re-routed, resulting in extensive cuts through the Nebraskan and Kansan glacial drifts. Several exposures of Aftonian peat were found between the two drifts. The locality at which collections were made is 4.9 miles west of Tama county line on U. S. Highway 30. The peat was prepared for microscopic study and one hundred and fifty plant microfossils were counted. Percentages were computed for each of the levels and the percentages show the abundance of the microfossils at each level. The distribution of the tree-pollens in the …
Petrography Of The Tertiary Igneous Rocks, Nigger Hill District, Wyoming-South Dakota, J. Robert Berg
Petrography Of The Tertiary Igneous Rocks, Nigger Hill District, Wyoming-South Dakota, J. Robert Berg
Proceedings of the Iowa Academy of Science
The Nigger Hill District, located on the Wyoming-South Dakota border in the northwestern Black Hills, is an area of Paleozoic sedimentaries, dipping outward from a central core of various alkaline and sub-alkaline Tertiary intrusive, and pre-Cambrian pegmatitic granite and schists. The Tertiary igneous rocks are of interest for three reasons: (1) they may furnish data that will contribute to the much debated problem of the origin of alkaline rocks; (2) when their structural relations are better understood, it will be possible to interpret more correctly the mechanics of their intrusion and the type of intrusive body they represent; (3) apparently …
Devonic Chronology In Iowa, Charles Keyes
Devonic Chronology In Iowa, Charles Keyes
Proceedings of the Iowa Academy of Science
The most important geological discovery in Iowa in recent years is the revelation that our Devonic deposition is not what it was long thought to be, that is, contemporaneous with the Devonic sedimentation of the East, or New York standard column. Instead of the two widely separated sections being of the same age, as always regarded, our Iowa Devonic rocks turn out to be very much younger than New York rocks. The two stratal successions appear now to have been laid down in altogether different geosynclines, and our western rocks were formed largely out of the ruins of the Eastern …
Glacial Marks, Arthur Goshorn
Glacial Marks, Arthur Goshorn
Proceedings of the Iowa Academy of Science
Opening a quarry on the southern edge of a Middle River bluff, the quarryman exposed 20 feet of the top layer of limestone. The top face of the limestone was covered with glacial scratches, hundreds of them running parallel north and south. The scratches marked the direction of floor of the ice. The valley of Middle River here is deep, and its course is east and west. A number of large boulders, house size, on the uplands on the south side of the river show that the valley must have been filled with ice when the boulders crossed the river …
An Esker-Like Deposit On The Middle Teton Glacier, L. R. Wilson
An Esker-Like Deposit On The Middle Teton Glacier, L. R. Wilson
Proceedings of the Iowa Academy of Science
During August of 1939 an esker-like deposit was observed on the surface of the Middle Teton Glacier in the Grand Teton National Park, Wyoming. The deposit, a slightly sorted gravel and clay ridge, was approximately three feet high, four feet wide, and one hundred yards long. In its north to south course over the glacier, the deposit extended over the top of a boulder that projected approximately eight feet above the ice surface. South of the boulder, the deposit lay in a shallow trough scoured in the glacier. Information received from the mountaineering guide indicates that upon the glacier more …
A Note On A Bolzano Function, Marian E. Daniells
A Note On A Bolzano Function, Marian E. Daniells
Proceedings of the Iowa Academy of Science
At a meeting of the Bohemian philosophical society in December 1921 Dr. Jasek reported the discovery among the papers of Bernhard Bolzano of a manuscript in which is described the construction of a continuous non-differentiable function. This function was devised more than thirty years before Weierstrass constructed his now well-known function. But while Weierstrass proved that his function possessed a derivative at no point, Bolzano showed the non-differentiability of his function only at a countable set of points everywhere dense. It is possible however to prove that the Bolzano function possesses a derivative at no point of the interval.
Exponential Operators, Fred Robertson
Exponential Operators, Fred Robertson
Proceedings of the Iowa Academy of Science
Introduction. The non-commutative operational formula Dx = xD + 1, where D = d/dx, is well known. The difficulty of determining the order of the operations x and D in a function f (x, D) retarded the use of operative functions. Bourlet1 was the first to discover a way to express an operative function, f(x, D) such that the operations with D always precede those with x. Thus his operators obey the laws of algebra and their operational meaning is unique.