Tractus Norwegiae Danicus Magnam Dioeceseos Aggerhusiensis

A striking 18th century map of the area around Oslo, Norway.

This finely engraved map of southeastern Norway, published in 1729 by the Imperial Geographer Johann Baptist Homann, provides an authoritative survey of the Great Diocese of Aggerhus. Centered on the vital administrative hub of Christiania (modern-day Oslo), the composition delineates the rugged interior, stretching from the Oslofjord to the Swedish frontier. The map meticulously identifies the region’s cities, religious institutions, and fortified garrisons, particularly those situated along the strategic course of the Glomma River.

The upper left features a decorative title cartouche, posthumously bearing Homann’s name, surrounded by a celestial cluster of winged putti. Notably, this specific example includes a contemporary manuscript inscription in old ink – Cum Privilegio Sac. Caes. Majestatio – reflecting the Imperial protection granted to the Homann firm prior to the notice being engraved directly into later states of the plate.

Occupying the right side of the sheet is an elaborate, large-scale vignette documenting the pre-industrial majesty of the Kongsberg Silver Mines. The scene provides a rare technical view of the complex machinery required for deep-earth extraction, including a dual-power system utilizing both a traditional waterwheel and a human-powered treadwheel to lift ore and manage groundwater. The cavernous, candle-lit interior and the network of ladders and ore carts offer an illustrated window into 18th-century mining engineering