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This thesis examines the ideological justification and conduct of the Pequot War (1636-1637) in Southern New England. It will address as a central issue the role religion played for the English in shaping their response to the challenges of colonization and resistance from indigenous tribes. The first chapter will serve as an introduction to the topic. Chapter's two and three will describe the events prior to and including the conflict in detail. Chapter four will discuss the religious underpinning of Puritan thought and policy. Chapter five will examine the military factors that made the destruction of the Pequot both possible and all but inevitable. Chapter six will conclude the examination and highlight the continued relevance of religion as a shaping force for policy and war.

The objective of this research is to understand and model the deformation and fracture response of materials exposed to water drop collisions. Due to the inherent complexity of the erosive response of materials exposed to a multiple water drop environment, this investigation concentrated on a very idealized water drop impact condition: the normal impact of a spherical water drop on a plane surface. The development of an experimental facility is described for producing spherical water drop impacts on materials at both subsonic and supersonic impact velocities. A reproducible, controlled, and well- characterized impact condition is necessary if an accurate assessment of the material's response is to be established.

The initial objective for this effort was to obtain an understanding of the response of ceramic materials on a microstructural level when subjected to water drop impact conditions (rain erosion). Before this objective could be satisfied it was necessary to have a well-controlled experimental arrangement so that the observed material damage, especially for very minor surface disruptions, could be related to a well-defined loading condition. A significant portion of the effort was devoted to achieving this test condition.

The objective of this research is to understand and model the deformation and fracture response of materials exposed to water drop collisions. Due to the inherent complexity of the erosive response of materials exposed to a multiple water drop environment, this investigation concentrated on a very idealized water drop impact condition: the normal impact of a spherical water drop on a plane surface. Impact experiments were conducted in a specially designed ballistic range facility capable of producing spherical water drop impacts on materials at impact velocities from 200 to 850/ms. A reproducible, controlled, and well-characterized impact condition is necessary if an accurate assessment of the material's response is to be established and this requirement has been satisfied within this program. The water drop impact damage on single crystal and polycrystalline calcium fluoride was also investigated. Some general observations are made with regard to the form of the fractures in extruded, hot-pressed, and press-forged calcium fluoride.

This investigation examines the analyses of solid particle erosion which have been formulated for both ductile and brittle materials. The solid particle erosion process can be described qualitatively for several materials from microscopic examinations of the eroded surfaces, however most of the available erosion analyses are based on material removal models which do not represent the physical processes of material removal as they are presently known. A number of published results have been generally accepted by the erosion community without proper scrutiny of the basis for the conclusions reached. Some of these inconsistencies are pointed out and the various analytical approaches used in describing solid particle erosion phenomena are summarized. The need for an adequately characterized solid particle erosion testing capability is indicated due to the range of test parameters which have been found recently to significantly influence the measured erosion rates. Meaningful advancement in the field is strongly dependent on the development of a reliable experimental data base and experimentation which isolates and clarifies a particular feature of the material removal process. (Author)

The damage to three-dimensional orthogonal carbon-carbon composites created by particle impacts ranging from 1800 to 6000/ms has been characterized for three weave constructions at both ambient and at temperatures up to 3500 C. The subsurface damage modes in the vicinity of the impact crater are described for the range of conditions investigated. Hypotheses are advanced concerning the failure modes and kinetics for the material ejected from the crater based on examination of sectioned specimens and high-speed photographic sequences. Penetration, compliance and plane-strain compression tests are utilized to supply mechanical characterization data for the dominant modes of failure, which are analyzed in terms of the dynamic stress states which develop in the three-dimensional composites during the collision cycle. (Author)

Single crystals of calcium fluoride, silicon, and magnesium oxide were subjected to quasistatic bead indentations from very low to moderately high load levels as reference for the dynamic loading conditions. 1 mm diameter beads were used in all of the tests reported here. Sapphire beads were propelled at velocities up to 100 m/s using a modified air gun arrangement which allows accurate placement of the particle on the surface, measurement of the impact velocity, and eliminates any rotational motions which would normally be imparted to the particle. Nylon beads were propelled at velocities up to 1000 m/s using an exploding wire impact facility. Single water drop impacts can now be obtained on these crystals at velocities up to 500 m/s, and multiple water drop experiments are carried out in a rotating arm erosion facility at velocities up to 260 m/s. Preliminary observations of the damage produced by water drop impacts on CaF2, Si, and MgO are described for impact velocities below the coherent fracture threshold, but the effects of solid particle collisions on these crystals are considered in greater depth. Significantly different damage modes and sequences are observed for CaF2 and MgO subjected to quasistatic sapphire bead indentations, sapphire bead impacts, and nylon bead impacts.

This program is directed toward an assessment of the effects of rain erosion damage on loss in transmission of radiation through window materials. The general influence of the progression of the material removal process on the spectral transmittance of polymeric materials (polymethylmethacrylate, polysulfone, polycarbonate, and nylon) and soda lime glass was evaluated for wavelengths from 0.5 to 2.1 microns. Erosion mechanism evaluations were made for the window materials (Chemcor, Cortran, spinel, and borosilicate glass) and the infrared transmitting materials (zinc sulfide, arsenic trisulfide, germanium, and sapphire), however mechanical difficulties were encountered in the AFML/Bell rotating arm apparatus before the transmittance measurements as a function of the exposure to the rain environment were completed. The materials evaluated were exposed to the standard rainfield of 1.8 mm water drops at an impact velocity of 730 fps.

While glass specimens behave in a characteristic manner when subjected to multiple collisions by glass beads, this behavior pattern cannot be associated with the erosion characteristics of all brittle or semi-brittle materials. On the other hand the general model is applicable to the erosion of any material which can be described in terms of a process of pit nucleation and growth and does not depend on the erosive environment. A demonstrated capability has been established in identifying the microscopic erosion mechanisms responsible for material removal and their relation to the microstructure of the material. Micromechanical models developed on the basis of the microscopic observations of the operative erosion mechanisms at various stages of the overall erosion process can then be incorporated into the general erosion model. This program is under development for describing the rain erosion of polymethylmethacrylate.

The stress and strain distributions around an initially coldworked hole in a plate and the subsequent redistribution of the stresses and strains when the plate is subjected to a uniform tensile loading are evaluated both analytically and experimentally. An elastic-plastic finite element idealization is developed for a one-quarter inch diameter hole in a 7075-T6 aluminum alloy plate one-quarter inch thick. Stress and strain distributions are provided for a 6 mil radial expansion of the hole and at tensile load levels of 10,000 lb., 25,000 lb., 37,500 lb., and 42,500 lb. Moire interferometry was used to verify that the elastic-plastic finite element analysis is representative of the strain distributions in an actual fastener coldworking procedure which involves inserting a cylindrical sleeve into a nominal one-quarter inch diameter hole and then drawing an oversized mandrel through the hole to produce a symmetrical distribution of residual stresses around the hole. Previous experimental strain evaluations of holes in plates involved hole diameters of at least one inch. The moire mismatch technique and photographic enlargements of the moire patterns provided the accuracy required. The conditions in the vicinity of the hole associated with the sleeve insertion procedure did not reflect the idealized conditions used in the finite element analysis which prohibited a valid comparison between the experimental and computed results. (Author)

An analytical approach to particle erosion of solid surfaces is developed based on a model of erosion pit nucleation and growth. The Hertzian theory of impact is used to introduce the kinematic and material parameters into this general statistical formulation of erosion processes. In order to minimize the number of unknown factors in the initial development of a predictive erosion theory, the particular case of solid spherical particles impacting directly on the plane surface of an elastic half-space is investigated. Erosion tests were conducted on the AFML-Bell erosion apparatus in conjunction with the modeling studies. The erosion mechanisms in fused silica was identified when eroded by multiple impacts of spherical glass beads. (Author)

The analytical model for the erosion of a brittle material by multiple particle impacts is revised in accordance with erosion tests conducted using liquid drops, 70 and 290 micron diameter glass beads, and uniformly-graded quartz sand impacting flat- faced specimens of boro-silicate glass directly and at an oblique angle and then microscopically examining the progressively- eroded surfaces. Weight-loss data are available for ultra-high molecular weight polyethylene, nickel-coated glass-fiber reinforced epoxy, and graphite-fiber reinforced epoxy specimens exposed to rain and sand erosion environments.