The Marion-Rural Retreat area of Smyth and Wythe counties, Virginia, contains the “missing link” to the long assumed, but heretofore unproven, continuation of the Pulaski fault trace southwestward around the structurally complex Marion dome area. The Seven Springs fault of Cooper (1936) has long been assumed to be the southwestward continuation of the extensive Pulaski fault; however, the linkage of these two faults was not established or understood. · Through detailed field mapping of mainly the Elbrook Dolomite, which is not known to exist northwest of the Pulaski fault block, and the time equivalent Honaker-Nolichucky succession, which is not known to exist southeast of the Saltville fault block, the writer has been able to delineate the trace of the Pulaski fault in this area. The fault shown on Butts' (1933) ”Valley Map” as extending east along the southeast base of Little Brushy Mountain from Marion to a point north of Groseclose, is not the Pulaski fault but instead a separate and distinct, high angle reverse fault called by Cooper (1936) the Hungry Mother fault. Near the center of the area, the Pulaski fault passes over the Hungry Mother fault and veers south away from the base of Little Brushy Mountain toward Atkins, Smyth County, Virginia, where careful mapping of the formations along the Valley of the Middle Fork of the Holston River affords a reliable criterion for joining the trace of the Pulaski fault with that of the Seven Springs fault. / Master of Science

This thesis is a socio-military history of a Confederate infantry regiment. Formed principally of Lynchburg City and Campbell County men, the Regiment fought in the Civil War as part of Kemper's Brigade, Pickett's Division, Longstreet's Corps, Lee's Army of Northern Virginia. Through diaries, letters, memoirs and contemporary newspapers, the writer has traced the Regiment from its inception as individual companies formed in reaction to John Brown's Raid until its surrender at Appomattox. The entire effort focuses, whenever possible, upon the officers and men of the Regiment. Thus, little attention is paid to grand strategy or national politics. Instead, drum rolls call the Regiment into formation for marches to unknown fields. The men fight in battles that later give the fields a place in history: First Manassas, Seven Pines, Frayser's Farm, Second Manassas, Antietam, Fredericksburg, Suffolk, Gettysburg, Plymouth, Drewry's Bluff, Cold Harbor, Bermuda Hundred, Five Forks and Sayler's Creek. Even in battle, the emphasis remains on the Regiment. Success or failure is measured by how the men felt they had performed, rather than whether or not the army achieved victory. The final result for the men of the 11th Virginia was defeat and surrender; yet, having suffered incredible hardship and having faced overwhelming odds, they emerged as rather heroic individuals. The thesis treats neither victory nor defeat, but men who gave their best for a cause in which they had complete faith. / Master of Arts

A single-degree of freedom rigid framed structure with variable loading is studied under the influence of five artificial earthquakes applied directly by use of the lumped-impulse numerical integration method and indirectly by converting the psuedo-accelero-grams of the artificial earthquakes into a half range sine expansion of the Fourier series by harmonic analysis. A comparison of the results obtained by each method is made for (a) an elastic system with no damping, (b) an elastic system with ten per cent of critical damping, and (c) an elasto-plastic system with ten per cent of critical damping. The objective of this study was to find through harmonic analysis a method to predict the approximate deflections of structures that might be caused by major earthquakes. It was found that the randomness of motion expressed by the psuedo-accelerograms does not permit generalizing the results of the harmonic analysis. / Master of Science

The creativity of 68 middle- and lower-class Caucasian preschool children attending a nursery school, kindergarten, or day-care center in Southwestern Virginia was measured by an object-identification originality test developed by Elizabeth K. Starkweather at the Oklahoma State University. Each child was tested individually by the investigator in an isolated room or special testing room. The Mann-Whitney U Test was employed to analyze differences, with a confidence level of .05. First born and only children were significantly more creative than later-born children. Middle-class children were significantly more creative than lower-class children. It was concluded that enrollment in a preschool program alone is not sufficient to increase the creativity of lower-class children to the level of their middle-class peers. It was also pointed out that some lower-class children were exceptionally creative and that further research into the home environments of these preschoolers might provide the answer to this puzzle. Experimental programs designed to increase creativity are needed to determine whether or not divergent thinking can be taught. / Master of Science

Master of Science

The design, fabrication and operation of a split Hopkinson bar apparatus is described. The theoretical basis for the experimental determination of material properties for materials subjected to high compressive strain rates using the split Hopkinson bar is discussed along with the assumptions made and their meanings. Some preliminary results for a lucite material are used to illustrate the type of information obtained from using the method. Limitations of the method and conclusions are discussed and recommendations are made. / Master of Science

Saline soils in the Dry Valley region of McMurdo Sound, Antarctica, contained bacteria showing salt tolerance or requirement. Soils were plated by the spread plate method on soil extract-peptone-yeast extract media to which sodium chloride had been added in concentrations from 0 to15 per cent (w/v). Bacteria isolated from these media at 2 °C, 5 °C, and 15 °C were predominantly Gram negative rods with few Gram positive rods and cocci. No filamentous fungi or Halobacterium spp. were observed on the media used. At 15 C there were no isolates from media containing greater than 15 percent added salt; however, counts of 1.4 x 10³ colonies per gram of soil were found at this concentration. As the incubation temperatures were lowered, salt tolerance was lowered. The data indicate that the limited soil microflora observed in saline soils and ponds may be attributed to a combination of low maximal summer temperature and high salinity. / Master of Science

The mycorrhizal association, known for its classic role in nutrient uptake, is shown to play an equally important role in the protection of seedlings against colonization by root-infecting fungi. This protection enhances the survival of seedlings. The survival of pine seedlings was tested in non-sterile and gnotobiotic systems when <i>Pisolithus tinctorius</i> and <i>Rhizoctonia solani</i> were added alone and in combination. When <i>P. tinctorius</i> alone was added to growth substrate of the pines, the survival of seedlings was greater than that of uninoculated controls. The increased survival of seedlings was probably due to a synergism between <i>P. tinctorius</i> and loblolly pine. If mycorrhizae were allowed to form on pine seedlings before <i>R. solani</i> was added to the growth substrate, survival was higher than treatments where <i>R. solani</i> alone was added or where <i>R. solani</i> and <i>P. tinctorius</i> were added simultaneously. The exact mechanism of the protection is unknown, but it is suggested that it might be any combination of resistance to penetration by root pathogens, mycorrhizae acting as sites of water and nutrient absorption during the period when the seedlings are susceptible to damping-off, production of antibiotics, and reduced growth stimulating chemicals in the rhizosphere. The effects of four fungicides, at two rates, on populations of mycorrhizal fungi were studied. In seedbeds receiving fungicides at low rates, the pine seedlings were larger and had fewer mycorrhizae than those in untreated seedbeds. In seedbeds receiving fungicides at high rates, the pine seedlings were smaller and had more mycorrhizae than the controls. The high rates of fungicides may have stunted the seedlings directly or may have selectively eliminated certain organisms, leaving others which were antagonistic to pines. The great numbers of mycorrhizae in seedbeds receiving high fungicide rates might have been due to the elimination of organisms that compete with mycorrhizal fungi. It should be possible to increase survival of seedlings in tree nurseries by mixing seeds with mycorrhizal fungi in the same way that legume seeds are inoculated with nodule forming bacteria. / Ph. D.

An improved first order linearized solution, describing the relative motion between an interceptor vehicle and a target vehicle in a circular orbit, has been developed by means of a transformation of the variables which occur in the differential equations of relative motion. The results of this analysis are compared with other first order solutions and with complete solutions obtained by numerically integrating the exact, nonlinear differential equations of motion. It was found that this improved first order method is considerably more accurate than the previously developed first order solutions, especially for large initial separation distances between the target and the interceptor. In order to fully utilize these results they have been applied to both the intercept and the rendezvous problem. In addition to the basic analysis, a method was developed to determine the time at which a velocity impulse should be applied to the interceptor in order that the total velocity impulse would be a minimum for both the intercept and rendezvous situations. / Ph. D.

Approximately 70 square miles of Roanoke, Botetourt, and Bedford counties and northern Roanoke were mapped in detail in an attempt to reconstruct the structural evolution of this critical area situated at the arcuate junction of the Southern and Central Appalachians. The area includes approximately 15,000 feet of Paleozoic sedimentary rocks which range in age from Early Cambrian to Early Mississippian. Most strata are allochthonous and comprise four imbricated thrust blocks delimited from northwest to southeast by the Pulaski, Salem, Max Meadows, and Blue. Ridge faults. Indigenous rocks comprise the Read-Coyner Mountain and Bonsack anticlinal fensters and a probable fenster in Roanoke. The Read-Coyner Mountain fenster effectively separates the Catawba syncline and related Pulaski block structures to the northwest from the Salem block to the southeast, whereas the Bonsack fenster intervenes between the Salem and Max Meadows blocks. The eastern part of the area contains salients of the Blue Ridge, Max Meadows, and Salem blocks and a cross-structure delineated by northwesterly trending allochthonous and indigenous structural elements. Reconstruction of pre-thrusting basin geometry from structural and stratigraphic evidence reveals the following arrangement of structural elements from southeast to northwest: (1) Blue Ridge anticlinorium, (2) ancestral Catawba syncline and related portions of the Pulaski block, (3) Read Mountain anticlinorium, now partially exposed in fensters, and (4) Blacksburg synclinorium. Stratigraphic evidence indicates that each of these structures evolved, at least in part, contemporaneously with deposition. Thrusting was probably initiated in Mississippian time with inception of the proto-Pulaski fault in the basement beneath the Blue Ridge anticlinorium. Subsequent thrusting apparently originated from within the proto-Pulaski and Pulaski blocks in a progressive sequence from northwest to southeast. The proto-Pulaski fault propagated from the basement to near the base of the Rome beneath the rooted Catawba syncline and then was deflected surfaceward along the southeastern flank of the Read Mountain anticlinorium. After initial movement by plunger-like stresses, the incompetent, structurally low Rome became detached from the sole of this thrust block and was left behind, while overlying beds continued to advance along the newly defined Pulaski fault. The Pulaski block was then forcibly shoved over the Read Mountain anticlinorium and into the Blacksburg synclinorium until it encountered the structural front to the northwest. Continued application of tangential stress through the impounded Blue Ridge anticlinorium and yoked Catawba syncline induced Salem thrusting within the Pulaski block over the southeastern flank of the Read Mountain anticline. The Max Meadows fault probably originated by resurrection of the original Rome-soled proto-Pulaski block over the Bonsack anticline. The final stages of thrusting probably involved movement of both the Max Meadows block and the dismembered anticlinal Blue Ridge block. After thrusting, both allochthonous and indigenous blocks were folded and locally faulted, and nearly 10,000 feet of structural relief was imparted on the Pulaski thrust and overlying Catawba syncline. The Tinker Mountain-Coyner Mountain cross-structure probably originated contemporaneously with deposition but developed largely after thrusting by vice-like lateral compression and contemporaneous downwarp generated in the structural, possibly primary embayment of the Roanoke area. / Ph. D.