diff --git a/TestGrid.md b/TestGrid.md
index 8d0bacb..7d33f81 100644
--- a/TestGrid.md
+++ b/TestGrid.md
@@ -1,7 +1,6 @@
-
 # The Public Test Grid
 
-This page is about the "Test Grid", which is also called the "pubgrid".  The pubgrid has several purposes:
+This page is about the "Public Test Grid", which is also called the "pubgrid".  The pubgrid has several purposes:
 
  * to make it easier for people new to tahoe to begin to experiment
  * to enable small-scale trial use of tahoe
@@ -12,8 +11,13 @@ The pubgrid also has two critical non-goals
   * The pubgrid is not intended to provide large-scale storage, and it is not intended to be reliable.   Don't store any data in the pubgrid if losing it would cause trouble.
   * Don't view the pubgrid as a free hundreds-of-MB backup service.
 
+## History
+
 Note that the introducer furl has changed recently (as of Feb. 2013).
 
+A version of the pubgrid existed until some time in 2012, when the introducer was lost.  In February of 2013, a new introducer was created, resulting in a change of furl.
+
+It is an interesting philosophical question as to whether the pubgrid with the new introducer is a different grid or not.  If servers that had been connecting to the new introducer are repointed to the new introducer, it can be considered the same grid with a change of introducer, with the property that files from the old grid may still be accessible.
 
 ## Cautions
 
@@ -26,7 +30,7 @@ URI:DIR2:ddg5n76x6stjb35psrcn7i3ytu:etbtnftlaeylm4gmi7mxzq6pg2ntgra7dyjeronyoo4p
 ## How To Connect To The Public Test Grid
 
 The test grid is subject to being updated at random times, so compatibility
-is likely to break without notice. Also note that many upgrades require all
+is likely to break without notice. Also note that an upgrade could require all
 files and directories to be flushed, especially as storage formats change.
 
 The test grid is currently running an 1.0.0-compatible release (allmydata-tahoe: 1.9.2) (see "My versions" on the welcome page for the current version of the web gateway server).
@@ -75,4 +79,4 @@ Suggested server setup:
 
 ## Contact Info
 
-If the pubgrid introducer appears to be down, either send an email to the tahoe-dev mailing list or contact PRab on irc://freenode/tahoe-lafs
\ No newline at end of file
+If the pubgrid introducer appears to be down, either send an email to the tahoe-dev mailing list or contact PRab on irc://freenode/tahoe-lafs