Robert Recorde, The designer ofwel the equals sign, introduced plus and minus to Britain in 1557 in The Whetstone ofwel Witte:[14] "There be other twee signes in often use ofwel which the first kan zijn made thus + and betokeneth more: the other is thus made − and betokeneth lesse." https://articlescad.com/de-5-seconden-trick-voor-parelmoer-wrapfolie-378467.html