Bridge of Sighs a translation from the Italian "Ponte dei sospiri" in the 19th century, comes from the suggestion that prisoners would sigh at their final view of beautiful Venice through the window before being taken down to their cells. In reality, the days of inquisitions and summary executions were over by the time the bridge was built, and the cells under the palace roof were occupied mostly by small-time criminals. In addition, little could be seen from inside the bridge due to the stone grills covering the windows. The name "Bridge of Sighs" has since been applied by association to other bridges
Greenhorn Limestone recognized in the Great Plains Region from Minnesota and Iowa to New Mexico to Montana and the Dakotas. In much of Alberta and Saskatchewan, the "Second White-Specked Shale" contains limy equivalents of the Greenhorn. In Kansas, the Greenhorn Formation is divided into the (lowest) Lincoln Limestone, Hartland Shale, Jetmore Chalk, and (highest) Pfeifer shale members, each noted by changes in chalkiness and limestone rhythmite patterns. In Colorado and western Kansas Hydrocarbon exploration, the divisions are Lincoln Limestone, Hartford Shale, and Bridge Creek Limestone. In other states, where the formation is less developed, the unit is not subdivided and is named