Britain did not convert to the Gregorian calendar until 1751, when 11 days had to be added to their dates to get the Gregorian dates. In 1639 they were 10 days behind the Gregorian calendar.
Re: Klein Tools Or Greenlee. Both Klein and Greenlee are TOP quality tools with a niche market. They have a few common tools (such as rabis and ratchet cutters) and either is worth buying over pretty much anything else. They are not really direct competitors. I prefer Knipex for most hand tools except linemans.
Rotary tools come with bits for carefully engraving, sharpening, cutting and sanding with the precision. With an engraving tool from Sears, you can make the clean cuts of a circular saw on a small scale thanks to a simple cutting disc.