The penny post and Valantin's card
Through out early 19th century, the industrial revolution of Britain brought rapid developments throughout printing and manufacturing technologies. Mass-production of Valentine's cards was simpler than ever, and soon was widely popular. It is estimated that about 200,000 Valentines had circulated in London alone by the mid-1820s. The success of Valentine's cards further increased in 1840, reports suggest that by the late 1840s the amount of cards being circulated doubled, doubling once again in the next two decades.