The first, in 1851, was a collection of early measurements; the second in 1852 correlated with Heinrich Schwabe's sunspot measurements, which had been made widely available in Alexander von Humboldt's Cosmos, also published in 1851.[11] With further data collected from the Toronto site, Sabine was able to demonstrate conclusively that the eleven-year sunspot cycle caused a similarly periodic variation in the Earth's magnetic field.[2] He presented a third and conclusive paper on the topic in 1856, "On Periodical Laws Discoverable in the Mean Effects of the Larger Magnetic Disturbances", in which he singled out the Toronto site for particular praise.[12]