These links are useful tools that can help with your ancestry research. Atlas History can help determine boundaries and dates in each state. Birth date calculators can assist you to calculate a persons age. The inflation calculator is a fun way to determine current value of something from a different time. The US Dollar Historical Value is similar but with more of a purchasing power angle. Weather history provides average weather conditions.
Atlas Hist County Boundaries
http://publications.newberry.org/ahcbp/
Birth Date Calculators
Calculator.net
https://www.calculator.net/age-calculator.html
Estimate Life Events Dates
http://www.godonthe.net/genealogy/EstimateLifeEventsDates.html
Day of Date Calculator
http://www.myrelative.com/html/day_of_birth.html
Calendar Converters
http://www.cyndislist.com/calendar.htm#Converters
Cousin & Relationships
http://www.cyndislist.com/cousins.htm#Charts
Geographical Names
http://geonames.usgs.gov/
Inflation Calculator
http://www.westegg.com/inflation/
US Dollar Historical Value
http://www.measuringworth.com/uscompare/
Weather History
http://www.weatherbase.com
Wolfram|Alpha
http://www.wolframalpha.com
Measurement Conversions for State-Land States
http://www.fmoran.com/measure.html
Land Measurement Conversion Guide
http://people.smu.edu/rjepsen/landmeasurements.html
Currency Converter
http://www.nationalarchives.gov.uk/currency/default0.asp#mid
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