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[letters][tone number 1-5]
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The direct link to www.shuowenjiezi.com fails the first time, because the site redirects you to the start page, where you have to click “enter the site”. After that, the direct link to the site will work (until you delete their cookies from your browser).
Both the database and the files for each graph are being updated frequently. However, the automatically generated files are often cached in browsers; in order to see changes, you might need to force your browser to refresh the page (reloading once or twice might work). This goes for the information files (like this one) as well.
The entries on graphical etymology use terms of which the meaning can be very specific. The terms are linked to this explanatory list of terminology.