Look out for improbable dates

To have a critical look at the dates in your genealogy database once in a while is a good idea. If you are looking at part of a pedigree you haven't viewed for a while, just start adding up and subtracting the numbers and evaluate the result. Look for dates that create improbable or impossible situations for your ancestors. Were children born in the same year, less than 9 months apart? Do the ages that events were supposed to happen add up? Were your ancestors married during childhood, or are women having children at an advanced age? 
All of these indicate that either the dates are wrong, or the people are misidentified. Poor math can also result in the skipping of a generation. 
  

To check for errors, you can use genealogical analysis programs like these: 

• The Genealogica Grafica tool does thorough tests on GedCom consistency, like finding subsequent births within 9 months.
• The website Bonkers can identify groups of claims that are inconsistent with each other.  
• Use FTAnalyzer to investigate your family tree and find errors like childrens birthdates before parent was born.
• Analyze is a command line program for displaying unconnected individuals in any GedCom file.
• GedCom View and Compare visualizes differences in the data of persons included in two GEDCOM files.
• GEDCOM Validator is a tool for checking a GEDCOM file for problems which could lead to data loss when transferring files between different genealogy applications.
• When submitting a GedCom file to the Ged-InLine website, a report is produced with warnings about deviations from strict GedCom.
• With GenMerge you can find possible double persons in a GedCom file and merge them, when needed. 
• The GedCom Service Programs checks GedCom files for duplicate entries and logical errors and allows a merging of duplicate persons. Additionally, a selection of a GedCom file can be exported, when you want to share only part of your data with someone. 
• With GedClean you can filter out living people from a GEDCOM file, creating a modified file for privacy purposes.

For more GEDCOM Software and Tools tools, see also Cyndi's List.

Een Nederlandse versie van deze pagina vind je op mijn Genealogie Bos Blog.

1816, "The Year Without a Summer"

Starting on 10-4-1815, a series of explosions of the Tambora vulcano triggered a 'Volcanic Winter' all over the world, ultimately causing the worst famines of the 19th century both in Europe and the USA. It also caused spectacularly coloured sunsets throughout the world, and global temperatures dropped by as much as 0.3°C in 1816.

The Tambora is one of Indonesia’s 130 active volcanoes, still standing at a gigantic 2800 m. on the northern Sumbawa Island. Prior to the enormous 1815 eruption it had shown no signs of volcanic activity for a thousand years.

On 10-4-1815, however, the first of a series of eruptions sent ash 20 miles into the atmosphere, covering the island with ash to a height of 1.5 meters. Five days late, the Tambora erupted violently once again, expelling so much ash that the sun was not seen for several days. The series of explosions continued for 4 months. 

Red-hot stones rained down after the grumbling volcano finally blew, and nearby settlements were completely engulfed in lava. Debris, particles and sulphur components were blown into the higher layers of the atmosphere. All vegetation on the island was destroyed by the noxious ash, and the resulting poisoned rain. Floating islands of pumice 3 miles long were observed before the coast, and even 4 years later these islands still hindered navigation. In all, so much rock and ash was thrown out of the Tambora that the height of the volcano was reduced by 1400 m. An astounding 70,000 people may have died in Indonesia as a result of burning, starvation, or poisonous gasses.