Editing Early evolution of the rules of baseball

== The Knickerbocker Rules of 1845 ==

The key rules can be thought of as:

* The field is what we now call diamond-shaped, with 4 bases that is 30 "paces" apart
* A match is decided by which team has the higher score at the end of a full inning in which one team has reached 21 "counts, or aces"
* Three outs define a half-inning
* Fair hits are those within the 90-degree fair territory, with no base advancement by batters or runners on foul hits
* Runners cannot be put out by plugging them with thrown balls
* Three strikes retires a batter
* A ball caught on the fly or on the first bounce retires the batter -- the "bound rule"
* Deliveries to a batter are "pitches," not throws, implying underhand deliveries

Apparently, the convention became to use teams of nine players in the early 1850s, but a formal rule was not adopted until 1858

Many common baseball terms, including "run" and "inning" are absent in these first rule, as are the size of a team, the pitching distance, and several running rules, including the idea of forceouts, tagging up, and stealing.

There is a reprint of the original set of Knickerbocker rules at 19cbaseball.com: [http://www.19cbaseball.com/image-knickerbocker-baseball-rules.html Major Rule Revisions, 1845-1870]

There is a [http://www.19cbaseball.com/rules.html more complete summary of rule changes] from 1845 to 1883 at 19cbaseball.com.

== Later changes ==

=== 1857 ===
* A game ends at nine innings; five innings define a legal game
* The pitching distance is put at 45 feet
* Runners cannot advance on caught flies

=== 1858 ===
* A club should field nine players
* The umpire can call strikes when, after a warning, the batter declines to offer at good pitches

=== 1860 ===
* The batter must hit from a specified zone

=== 1863 ===
* Umpires can, after a warning, call balls; the batter is awarded first base, and other runners advance one base, after three called balls

=== 1865 ===
* Fair balls caught on the first bounce are no longer considered outs