In 1728, Augustus II the Strong erected the "Royal Cabinet of Mathematical and Physical Instruments" in the Royal Palace at the Zwinger in Dresden as an independent museum that collected tools and scientific instruments for calculating the altitude of stars or the next solar eclipse, or for aligning cannons. Until today, the Salon houses numerous showpieces from the world-famous collection. It includes terrestrial and celestial globes, fascinating optical, astronomical, and geodesic devices, and historical aids for calculating, drawing, and measuring. The new museum guide takes readers and/or visitors through the large exhibition, which reopened in 2013, documents the sovereigns’ passion for collecting, and shows laypeople and specialists the foundations on which our world of today is based.