Abstract: A book marker useful to mark a page in a book as well as hold a page down while the book is being read is disclosed. The device has a frame which supports and guides a pair of cover engaging members. These markers have elongated C-shaped portions which hook over the upper and lower edges of a book cover and are biased towards one another. An arm is pivotally attached to an outer corner of one of the C-shaped portions. The end of the arm has a swingable page marker extending over the page of the book. Preferably this page marker is a thin stiff wire that minimizes any obstructions to reading the book. The arm is spring loaded causing the page marker to press against the page. This page marker can be swung out of the way when desired, for example when the book is first mounted or when a great number of pages are to be advanced. The device assists the reader by keeping the pages on one side of the book held down during reading, as well as marking the place when the book is closed.

Abstract: A pressure-type containment device with an improved lid sealing feature is disclosed. A lid disk seats on a shoulder along the interior wall of a container mouth and is held in place by a fastening ring adapted to fit into the container mouth. A resilient gasket, such as an O-ring, is wedged between the fastening ring and the lid disk along the interior wall of the mouth. The margin of the fastening ring confronting the gasket is tapered to urge the gasket against the interior wall. A pressure increase within the container expanding the lid disk causes compression of the gasket, enhancing the seal.