Postcard sent by Christophe (France). It seems that if you wash a cow in a washing machine, and then hang it outdoors in the clotheline... It become a sort of sheep and then you can knit its wool. Not sure about temperature, though, because it indicates 30, 60 and 95 ºC.
Arrived the same day (funny, isn't it?): postcard sent by Heleen (the Netherlands). It shows the typical breed of sheep in Drenthe, in the east of the Netherlands. It arrived with these two wool-related stamps: De Schapenscheerseter (naar Millet) (1889) and Weefgetouw met wever (1884), both by Van Gogh.