Blesson also observed differences in the color and heat of the flames in different marshes. The ignis fatuus in Malapane, Upper Silesia (now Ozimek, Poland) could be ignited and extinguished, but were unable to burn pieces of paper or wood shavings. Similarly, the ignis fatuus in another forest in Poland coated pieces of paper and wood shavings with an oily viscous fluid instead of burning them. Blesson also accidentally created ignis fatuus in the marshes of Porta Westfalica, Germany, while launching fireworks.