McGill University Thèses et mémoires publiés en 1950

The aim of the historical geographer is to reconstruct and interpret past landscapes (i.e. the physical and cultural aspects of the surface of the earth) at significant cross-sections in the historical development of a region. The landscape at any point of time is the result of the historical processes gone before, and will itself change, with time, into a new landscape with different physical and cultural characteristics. The historical geographer thus hopes to explain the development of each landscape, including that of the present, and its transformation into the next. By means of maps and diagrams, comparisons can be made …  Lire la suite

Genetic information gained through the study of the inheritance of growth pattern and their certain body characteristics in reciprocal crosses of Broad Breasted Bronze - Charlevoix turkeys should provide a basis for the development and improvement of a small type of turkey such as the Charlevoix. Any inherent study of this kind must be carried through at least a three year period, to allow for the necessary reciprocal crosses within the progeny of the initial mating to bring forth Inherent differences existent within the parental types. The results which are presented in this thesis are therefore representative of the FI …  Lire la suite

Jamieson, R. (Supervisor)  Lire la suite

There are, depending on the student's interest, many ways to view an industrial enterprise as, for example, a factory or a department store. The general economist may see it as a productive unit within a supply and demand frame of reference; the labor economist, as a collective bargaining unit within the frame of reference of a theory of wages; and the student of business administration may see it in terms of an organizational chart. Each of these points of view may be a legitimate way of regarding the phenomenon but each is incomplete - important elements may be neglected.  Lire la suite

It is now generally recognized that the processes involved in a chemical reaction are frequently not as simple as the stoichiometric equation would indicate, but consist rather of a series of elementary reactions of simple order; the over-all reaction observed is the net effect of the several elementary stages. A knowledge of these elementary reactions is therefore essential in the elucidation of the over-all reaction mechanism. Very often these elementary steps are reactions which involve free atoms or free radicals, entities which have only a transitory existence, but which nevertheless play an essential part in the course of the reaction.  Lire la suite

Helminthosporium sativum P.K. & B. causes a disease of barley affecting the seedlings as well as the roots, leaves and heads of mature plants. This disease results in an annual reduction in barley yield and is at least partially responsible for fluctuations in yield from year to year and for the restriction of the present barley growing area. The exact amount of loss, however, is difficult to estimate, and often is attributed to factors other than this disease. Machacek (1943) stated that the common root rot of cereals and grasses was widespread in Manitoba.  Lire la suite

This paper is concerned with an investigation into the absorption characteristics of an absorbent screen, consisting of a thin, partially conductive cloth, separated from a plane metal surface by a dielectiric of constant thickness. A method of measuring these characteristics is described and experimental results are presented which relate reflected power to the angle of incidence for screens employing either air or masonite as dielectria. A theoretical treatment is based on the transmission line analogy of plane wave radiation in free space and leads to the use of simple charts for computation of power reflection coefficients.  Lire la suite

J.J. Thomson in his publication “Recent Researches” of 1895 mentions the existence of electromagnetic waves in metallic cavities. This seems to be the first reference made to cavities as we know them today. Sir Oliver Lodge demonstrated their use as resonators in the following year. Lord Rayleigh in 1897 showed that there were two types of modes possible and proved that each mode type had a definite cut off frequency, and that propagation is possible only if the frequency is higher than this limiting value. In 1902 Becker did some experimental work at wavelengths of 5 and 10 cms. The …  Lire la suite

This report is based on field work by the writer during the summers of 1948 and 1949, and on subsequent laboratory investigations at McGill University. The map-area forms part of a concession in New Quebec granted to the Hollinger North Shore Exploration Company Limited. The concession includes part of the “Labrador Trough” which contains a folded and faulted assemblage of Precambrian sedimentary and volcanic rocks (Figure 1). The first part of the report deals with the general character of the country and the regional geology. The second part is concerned with a detailed study of part of the Kanispiskau system …  Lire la suite

The effects on the capacity and thermal efficiency of spray drying equipment resulting from variations in rate of inlet air, inlet air temperature, feed temperature, nozzle location and degree of atomization, were investigated in a down-flow, vertical spray drying chamber, 5 feet high and 4 feet in internal diameter. A two-fluid atomizing nozzle was used. The results obtained during the evaporation of water alone were compared with the drying of an actual solution under similar operating conditions. Results showed that capacity and efficiency passed through a sharp maximum at optimum values of the operating conditions and that the latter bed …  Lire la suite

Aircraft antennas for MF and HF Communications have been a problem throughout aeronautical development. In late years, VHF for short range communication has considerably relieved the lower band use, but an important requirement still remains for long range HF communication, and for MF in special areas. Military flying places more stringent demands upon band use than does civil flying, because more frequencies are required for liaison and command Communications, to coordinate large numbers of aircraft on different missions from different bases.  Lire la suite

The peripheral circulation has long been an object of intense study. Besides its obvious medical importance, for example, in shock and hypertension, it is a fundamental factor in the integration of the various organs of the vertebrate body. A great amount of knowledge has been obtained by indirect means, such as the effects of various pharmacological agents on the blood pressure or on the rate of flow through isolated perfused organs. In addition, a number of ingenious techniques have been developed for the direct observation of the peripheral circulation. In all such studies the peripheral circulation is of interest as …  Lire la suite

It would be unfaithful to Croce's own principles to attribute to the historical genesis of his philosophy excessive importance. But though one must recognize that it is not a mere product of circumstances, it is necessary to grasp the nature of the background against which it arose. Only then will its polemical character become apparent, and only then will it assume the place due to it in the chain of philosophical progress. We must not attempt to consider his philosophy of history as a system to be connected with other systems; the changing, prolific nature of Croce's thought as well …  Lire la suite

When Hamilton had invented quaternions, the question arosewhether they could be used to advantage in mathematical physics.However, the world then only had three dimensions, and so thescalar part of the quaternion was suppressed, the resultingentity being called a vector. The relation between vectoranalysisand quaternion algebra is well known, and need notbe entered into here.  Lire la suite

When Hamilton had invented quaternions, the question arose whether they could be used to advantage in mathematical physics. However, the world then only had three dimensions, and so the scalar part of the quaternion was suppressed, the resulting entity being called a vector. The relation between vector-analysis and quaternion algebra is well known, and need not be entered into here. With the theory of relativity also came the fourth dimension. Although Minkowski himself rejected the quaternionic calculus as “too narrow and clumsy for the purpose in question”, Silberstein has strongly advocated the cause of quaternions. He used quaternions with imaginary …  Lire la suite

When Hamilton had invented quaternions, the question arose whether they could be used to advantage in mathematical physics. However, the world then only had three dimensions, and so the scalar part of the quaternion was suppressed, the resulting entity being called a vector. The relation between vector analysis and quaternion algebra is well known, and need not be entered into here. With the theory of relativity also came the fourth dimension. Although Minkowski himself rejected the quaternionic calculus as "too narrow and clumsy for the purpose in question", Silberstein has strongly advocated the cause of quaternions. He used quaternions with …  Lire la suite

A brief review of the contemporary investigations of Keuthe, Keenan, Neumann and others is presented and forms the basis for enlargement of the theory to cover more cases than in the past. A general momentum equation is introduced which is adaptable to either constant area or constant pressure mixing and more generally to all cases of constant pressure gradient mixing. The author's experimental work substantiates this theory and shows that the losses for any one geometrical design are approximately a constant proportion of the relative dynamic head. The theory for the turbulent mixing of free jets is derived and applied …  Lire la suite

Recent investigation, that of the last half century, of the velocity of sound in air has shown that methods using sources of continuous sound of fixed frequency, which could be performed on a laboratory scale where humidity could be controlled and relatively dry air used, tended to result in higher values for the velocity at zero humidity than those obtained from determinations using sound pulses which were carried out in the open air with usually much higher water vapour content.  Lire la suite

The importance of the brain as the essential basis of intelligent behavior is taken for granted by modern psychology. Although no text-book would claim that even the principal relationships between brain function and intelligence have been adequately formulated, modern research assumes that a detailed and comprehensive account needs only time and continued effort for its ultimate appearance. The conflicting views in the contemporary literature on the physiological basis of intelligence probably reflect differences of method - for example, what experimental subjects are used, - as well as differences in theoretical assumptions.  Lire la suite

The present report describes a study made at McGill University from 1948 to 1950 on the solution polymerization of styrene with stannic chloride in the presence of carboxylic acids and other proton-donor cocatalysts. The carboxylic acids that were used in this investigation were acetic, mono-, di- and trichloroacetic acids. In addition, the effects of water, pentachlorophenol, trinitrophenol and hydrogen chloride were examined. The reaction was studied in toluene and in chlorobenzene solutions.  Lire la suite

The potentialities of catalysis were foreseen by Ostwald when he prophesied that a scientific knowledge and control of catalytic phenomena would lead to immeasurable results technically (1). This prophecy has been fulfilled, for to-day the importance of catalysis in science and industry is recognized by chemists everywhere. The petroleum industry in particular has assisted greatly in this development and has made notable contributions.  Lire la suite

A detailed description is given of a test rig that reproduces in an idealized form the same conditions existing in the piloting region of a continuous combustion system and allows the effects of certain variables to be examined under definable conditions. Tests to determine the effects of air-fuel ratio, atomization, and turbulence, on the combustion and spontaneous ignition delay-temperature relationship of standard aviation kerosene are described.  Lire la suite

The factors in nature which influence population changes are so numerous and so complex that it seems that the only hope of understanding their interrelations lies in a thorough knowledge of how each factor operates separately upon the population. Having assessed the value of each agent by itself we may look to the biomathematician to describe their interdependence. Population changes depend upon nutrition, weather, competition between species, fecundity and the incidence of disease, parasites and predators.  Lire la suite

This investigation was carried out at the instigation of Dr. W. V. Cone in the attempt to discover chronic pathological changes in oligodendroglia. Knowledge of chronic changes in the oligodendrocytes has not been greatly advanced m the past twenty years. At that time it was stated that: "Unlike astrocytes, the disappearance of myelin does not result in an increase but a decrease of the oligodendrocytes and it is quite possible that with myelin degeneration oligodendrocytes are transformed into astrocytes." (Penfield 1932).  Lire la suite

The understanding of the functions of a certain portion of the cortex ultimately is dependent on a knowledge of the connections or interrelationships of that particular cortex. Consequently, the visual cortex and the auditory area are better understood because of the works of Poliak (1932), Talbot (1942), Talbot, Woolsey and Thompson (1946), and of Walker (1937a,1937b), of Ades and Felder (1942, 1945), Ades (1943), Woolsey and Walzl (1942), Walzl and Woolsey (1943), Tunturi (1944, 1945), Rose (1949), and Rose and Woolsey (1949).  Lire la suite

Those specific autocatalytic enzyme-like entities which we call genes are responsible for the ultimate structure and organization of the developed organism. The mode of action of the genes in producing the phonotype is no doubt intricate, and the action of each gene involves a continued sequence of individual reactions, each new step based on the preceding one. To learn how organisms attain their final structure, we must investigate the nature of these chains of reactions, and this is one of the concerns of Physiological Genetics.  Lire la suite

Considerable evidence has been advanced in the literature that rutin, and other vitamin P-active materials, act as antioxidants. The beneficial effect of some of these materials on vitamin C has been shown, but the results have been predominantly qualitative. This study, involving the administration of vitamin C to 128 guinea pigs, was designed to determine the extent to which rutin enhanced the apparent biological value of ascorbic acid. The odontoblast method of vitamin C bioassay was used. Rutin increased the apparent biological value of ascorbic acid by approximately 50%, when the vitamin was supplied in suboptimum amounts for normal tooth …  Lire la suite

The Palaeozoic plant collection dealt with in this paper comprises specimens collected by Sir J. William Dawson who was principal of McGill University from 1855 to 1893. One of Canada's most distinguished geologists of the nineteenth, Principal Dawson pioneered paleobotanical investigations in North America. Much subsequent work, particularly in the coal fields of Eastern Canada, has been based on the discoveries of this famous scientist. Unfortunately, however, since the death of Sir William Dawson, no systematic restudy of this collection has been made.  Lire la suite

Migration from the parental home, and a shift from parental dependence to an independent occupation is characteristic behaviour of modern youth. The main problems of this thesis are the extent to which young people leave their home community, the occupations they enter, and the influences which affect these decisions. Choice of occupation represents one of the two main decisions made by a person in his lifetime. This decision does much to determine the individual's life; the type of work he does and the remuneration he receives influences his home, his clothes, his leisure time, and in many cases, even the …  Lire la suite

It has been known for some time that D-fructose condenses with methanol in the presence of hydrogen chloride to give a syrup consisting in the main of equal amounts of methyl a-and b-D-fructofuranoside. Earlier workers have isolated a portion of the a-isomer as a pure, crystalline compound, but the b-analogue has never been separated in a pure form. In view of the configurational relationship to sucrose of the latter isomer, attempts have been made to study the chemistry of this isomer and to obtain it in pure form.  Lire la suite

Data pertaining to this thesis originate, mainly, within an area referred to as the Joannès-Malartic sector of the Quebec gold belt. More specifically, the area may be defined as extending eastward from the western boundaries of Vaudray, Joannès and Cléricy Townships to the eastern boundaries of Fournière, Malartic and La Motte Townships, and northward from latitude 48° 00' to latitude 48° 26'. In all, the Joannès-Malartic sector embraces an area of approximately 1,200 square miles. A map compiled by the writer showing the main formations within the thesis area and the structural data pertaining to them will be found at …  Lire la suite

Ilford Nuclear type plates loaded with uranyl acetate were exposed to 78 Mev. protons inside the vacuum chamber of the McGill cyclotron, and tracks from the resulting uranium fissions observed under high magnification. Bathing the plates in a very weak solution of chromic acid before development materially reduced the background of alpha tracks from the spontaneous disintegration of uranium and of fog due to the proton beam. A concentration of 0.13 mgms. of CrO3 per ml. of water inhibited development of the proton and alpha tracks, but left the fission tracks quite dense. Fission tracks in these plates appeared similar …  Lire la suite

Radar has found one of its most useful applications in the investigation of atmospheric phenomena. Several new problems are introduced when the structure and mechanism of rain showers are studied using radar as a research tool. These problems necessitate the modification of existing theory on rain showers. Radar echoes from showers, associated with a cold front, produce a bright line on the radar screen at a height which corresponds to the freezing level of the shower.  Lire la suite

De tous les genres littéraires, le roman est celui qui reflète le mieux la vie et la civilisation d'un pays ou d’un peuple. Qu'il le veuille ou non, le romancier fait plus ou moins consciemment, le tableau des habitants, de l’esprit et des coutumes du milieu qui l’intéresse, mais l'authenticité de ce tableau varie selon ses connaissances, son talent et son but. Cette thèse se propose de faire le tableau de la vie des campagnes du Canada-Français d'après les romans canadiens-français parus entre 1837 (date de publication du Premier roman) et 1900.  Lire la suite

For single crystals of graphite the conductivity is of the order of that of a poorly conducting metal, and as in the case of a metal the temperature coefficient of conductivity is negative. The following theory of metallic conductivity was first developed by Riecke, Drude, Lorentz and others: Consider a metal containing N electrons per unit volume and suppose that each electron can move freely for a mean time 2 tau, after which it suffers a collision and its momentum is destroyed. (tau is "time of relaxation”).  Lire la suite

During the summer of 1949 an investigation of the aerobic bacteria found in the intestines and slime of pike (Esox lucius) was commenced. The fish were obtained, by the use of gill nets, from Lake Monroe, an unpolluted lake, in the Mont Tremblant Park region of the Laurentian Mountains in Quebec. Seventeen pike were used in the study. The length and weight of each fish and the depth and temperature of the water from which the fish were taken are given in Table I.  Lire la suite

Chapman (4) observed that the levels assumed by a population of poikilothermic animals depended upon the 'resistance' that the environment presented to the 'biotic potential' (ability of organisms to survive and reproduce) of the organisms of that population. He postulated that a modification of Ohm's law for electrical resistance could be used in the calculation of the resistance that any environment presents to a species. Thus the degree to which various environments affect the biotic potential of a species could be expressed by a series of exponential factors.  Lire la suite

The Ymir area (long. 117° - 117°15’, lat. 49°15'- 49°30') lies just southeast of Nelson in the southern part of British Columbia. It includes 300 square miles of the area lying between Kootenay Lake and the Columbia River (Figure I). The western part of the area is easily accessible from the Ymir-Salmo road which runs nearly north-south along the western border of the map area. A branch line of the Great Northern Railroad follows along this road.  Lire la suite

During the summer of 1949 the writer carried out exploration work on a group of eight mining claims, known as the McCuaig group. These claims are located in Pardee Township, Thunder Bay District, Ontario. The property may be reached by means of a gravel road two miles long that branches off to the north from the Scott Highway at a point forty miles west of Fort William. The Scott Highway is a paved highway between Duluth, Minnesota, and Fort William, Ontario.  Lire la suite

Whenever an evacuated solid is exposed to a gas, a part of the gas is taken up by the solid. If the process is true surface condensation, it is known as "adsorption". This is not to be confused with the term "absorption", which refers to a more or less uniform penetration of molecules into the molecular structure of the solid. McBain has proposed the term "sorption" to include cases where more than one process is occuring or those in which the exact nature of the process is yet unknown.  Lire la suite

Photosensitization by resonance radiation is the process involved when an atom, optically excited by absorption of resonance radiation, transfers this energy by collision to another atom or molecule, thereby inducing a chemical reaction. Collisions in which energy of excitation is converted either into other energy of excitation or into kinetic energy are termed inelastic collisions of the second kind. Numerous examples of this type of reaction have been observed and the method has proven to be a powerful tool in elucidating the mechanisms of free radical and atomic reactions.  Lire la suite

Cleghorn, R. (Supervisor)  Lire la suite

The marked growth of medical knowledge in the past hundred years has produced a wide range of modifications in medical practice. Habits and attitudes peculiar to medical practice have changed. Medical practice has become dependent upon a wide range of elements. Organizational or bureaucratic (1) devices have been utilized to help gain control over these factors. The utilization of bureaucracy in medical practice has introduced new contingencies which have the potential of interfering with high-standard medicine. Inter-dependence between medical practice and other elements of our culture has been greatly increased. The elements peculiar to a medical career have been considerably …  Lire la suite

The present investigation arose out of a study on blood preservation which was begun in the Department of Biochemistry at McGill in January, 1940 by Collip and Denstedt. In the course of the investigation it became necessary to evaluate the efficiency of various methods of preservation and the viability of the preserved red cells. The only satisfactory method at that time, and even at the present date, was to transfuse the preserved blood and follow the elimination of the donor cells from the circulation of the recipient.  Lire la suite

Probably one of the greatest contributions to the field of chemical kinetics was the proposal made by Arrhenius in 1889 that in a chemical reaction an equilibrium exists between inactive and active molecules of the reactant and the latter only were able to take part in the reaction. By applying the reaction isochore to the equilibrium between inactive and active species the variation in the reaction rate with temperature is found to be ln k = ln A - E/RT (1) where E represents the difference in heat content between active and inactive molecules and A is a term which …  Lire la suite

“There is a peculiar disorder of the breast marked by stormy and peculiar symptoms, considerable because of the danger belonging to it- the seat of it, and the sense of strangling and anxiety with which it is attended may make it not improperly called angina pectoris” (96). This is the opening remark of a paper entitled “Some Account of a Disorder of the Breast” read by Heberden before the Royal College of Physicians in 1768. It was not long after this, in 1799, that Edward Jenner correctly interpreted John Hunter’s fatal malady as a disease of the coronary arteries (157). …  Lire la suite

The use of pasture is an established practice in poultry management. Growing stock are generally reared on grass range and, on many farms, the laying flock is allowed access to pasture during the summer months. It is considered that the forage, insects, and other natural sources of feedstuffs, which are available to birds on range, make a useful contribution to the poultry diet and act as an insurance against a possible deficiency in the ordinary ration of grain and mash. It is also considered that the fresh air, sunlight, and sanitary conditions, enjoyed by birds on pasture, promote good health …  Lire la suite

During the period since the popularity of uncritical explanations of behavior in terms of instinct began to wane among psychologists, a number of writers have suggested that hunger, or in behavioristic terms the tendency of animals to select and eat an adequate diet, is at least in part the result of learning (Green, 1925; Harris et al., 1931; Scott, 1947; Ghent, 1949; and Hebb, 1949). The present paper describes an experiment designed to evaluate the role played by learning in the development of the specific hunger for potassium.[...]  Lire la suite

The most general charge laid against Kant for many years was that of inconsistency. The aim of this thesis is to show that some of the greatest difficulties in Kant’s Ethics are due to his attempt to be too consistent - to his attempt to expound his moral theory in the metaphysical terms of the First Critique. That this attempt fails and that, nevertheless, the greater part of Kant’s moral philosophy is not thereby invalidated, is proof of the worth and strength of the latter. How far grounds for the rejection of Kant’s metaphysical system are provided by the incompatibility …  Lire la suite