- Silurian (Wikipedia)
The Silurian (/sɪˈljʊəriːən, saɪ-/ sih-LURE-ee-ən, sy-) is a geologic period and system spanning 24.6 million years from the end of the Ordovician Period, at 443.8 million years ago (Mya), to the beginning of the Devonian Period, 419.2 Mya. The Silurian is the shortest period of the Paleozoic Era. As with other geologic periods, the rock beds that define the period’s start and end are well identified, but the exact dates are uncertain by a few million years. The base of the Silurian is set at a series of major Ordovician–Silurian extinction events when up to 60% of marine genera were wiped out.
- Seattle Neighborhoods: Loyal Heights, Sunset Hill, and Shilshole — Thumbnail History (historylink.org)
The Loyal Heights neighborhood began in 1890 as a bedroom suburb of the town of Ballard and continues the same role in the northwestern corner of contemporary Seattle. The area is situated above NW 65th Street, well north of Ballard’s primary commercial district. The shores of Puget Sound and 15th Avenue NW define its western and eastern boundaries, and the former city limits at NW 85th Street define its northern extension. Loyal Heights owes its name and a large part of its existence to a migrant mid-westerner, Harry W. Treat (1865-1922), who developed and promoted a large tract of land above NW 75th Street, beginning in 1906.