Drift dispersal in central Southern Ontario /

Two tills are readily identi-f i able in central Southern Ontario, a very stony, loose deposit o-f variable matrix (Dummer till) and a moderately stony, fissile and compact deposit that is more homogeneous (drumlinized till). The quantity o-f Precambr i an, Paleozoic and Shadow Lake Formation (Paleozoic) rock types were determined and corresponding isopleth maps drawn. The changes in lithology content occurred in the direction o-f transport, there-fore, compositional isopleths o-f till may be considered equipotential lines for the reconstruction of glacier flow paths. Areal gradations of drift lithology indicated that the prime agents of dispersal were ice and glacial meltwaters. The down-ice abundance trend of till components indicated a dispersal pattern showing the concentration of a given lithology type peaking within a few kilometres of the source followed by a rapid decline and thereafter, a more gradual decrease with increasing distance. Within the esker deposits, igneous rocks may form the major component and can extend further onto the limestone plain than in the adjacent till. Evidence is presented that indicates the "style" of dispersal was one in which glacial ice may have been strongly influenced by local bedrock topography and the regional structural trends. The ice tended to follow pre-existing valleys and lows, depositing till composed mainly of local bedrock. Gradations in Paleozoic clast content showed that the local bedrock lithology became the primary till component within 3 km of down-ice transport. Evidence is presented that indicated the last glaciation may have occurred as a relatively thin ice mass, followed by stagnation and recession. No evidence of a lateglacial re-advance was found within the study area. Because of the lack of a contact between the Dummer and drumlinized till, and because of results showing gradation of the Dummer till into the drumlinized till (as indicated by lithology content and grain size), it is suggested that no re-advance occurred.

Quadtree representation and compression of spatial data

Spatial data representation and compression has become a focus issue in computer graphics and image processing applications. Quadtrees, as one of hierarchical data structures, basing on the principle of recursive decomposition of space, always offer a compact and efficient representation of an image. For a given image, the choice of quadtree root node plays an important role in its quadtree representation and final data compression. The goal of this thesis is to present a heuristic algorithm for finding a root node of a region quadtree, which is able to reduce the number of leaf nodes when compared with the standard quadtree decomposition. The empirical results indicate that, this proposed algorithm has quadtree representation and data compression improvement when in comparison with the traditional method.

John Burtniak Postcard Collection

326 images (b&w and col.) mounted on 54 poster boards ; 64 x 36 cm or smaller. 4 compact disc

Gideon Sundback fonds, 1942, 1952, 1985-1986, 1991, 2004, n.d.

Gideon Sundback was born in Stockholm, Sweden in 1880. He was educated as an engineer and settled in the United States in 1905. While working for the Universal Fastener Company, New Jersey in 1913 he developed and patented a “separable fastener”, which improved on an earlier version of what today is known as the zipper. He later moved his family to Meadville, Pennsylvania and sought a Canadian location for the production of his new invention. He settled on St. Catharines as it was an easy commute from his Pennsylvania home and opened The Lightning Fastener Company on Niagara Street. Sundback died on June 21, 1954 and is interred in Meadville, Pennsylvania. The plant continued to operate, but with increased foreign competition the manufacture of the zipper declined. The plant closed in 1981. Source: The St. Catharines Standard, July 3, 2004 Harold Fox was a noted lawyer, academic, businessman, author and a leading authority on intellectual property. He was engaged by Gideon Sunback and the Lightening Fastening Company to combat patent infringements by Colonial Fastener in the 1930s. The relationship continued when Fox was asked to become the managing director of the company, which he did until 1949. Fox lived in St. Catharines at his home “Foxcroft” until his death in 1969. Source: http://thefoxfund.com/harold.htm (November 2, 2009)

Daguerreotype - Julia Canby Cleveland and her Doll

Daguerreotype of Julia Canby Cleveland and her doll. Both the doll and the girl have wide brimmed hats. The photograph is in an ornate wooden (compact-like) case with carved thistles. There is a latch on the case. The case is lined in velvet and the leather binding on the spine has come away.