Shabbos, Mishnah 5. Our mishnah continues to deal with the melachah of writing, and it lists a series of cases in which the writer is not liable: because of the writing material, because of the manner of writing, and because of the result.
Writing with materials that do not last:
One who writes not with ink, but with one of the following:
"Mei peiros" - fruit juices, such as the juice of grapes or of berries and the like.
"Avak derachim" - he wrote with the dust of the road.
"Avak ha-deyo" - the dried ink powder that collects in the inkwell, which he took and wrote with.
And the same applies to any other substance, where either the ink itself does not last, or the material on which one writes does not last.
Unusual manners of writing:
One who writes "b'gav yado" - with the back of his hand.
One who writes "b'raglo" - with his foot.
One who writes "b'fiv" - with his mouth.
One who writes "b'marpeiko" - with his elbow, or with the joint of his arm.
In all of these cases the mishnah rules that he is exempt, since this is an unusual way of writing.
Writing that does not amount to two letters:
We learned that liability applies to one who writes the equivalent of two letters. What is the law when two new letters were not written?
"Hameshalim os achas" - one who completes a single letter: there was already writing in front of him, and he completed it by writing only one letter; that is not enough.
"Hamechadesh kesav shenimchak" - one who refreshes writing that has been erased: there was writing in front of him that had partly rubbed away, and he wishes to freshen it and writes over it; this too does not suffice.
The same is true of one who intends to write only a single letter and wrote two zayins: this letter, as written in a Sefer Torah, is in fact made up of two zayins, and that is how it looks. If somehow he did not connect them, and he is left with two letters, since his intention was for only one letter, he is not liable.
Two letters that are not read together:
He wrote "os achas bakarka v'os achas bakorah" - one letter on the ground and one letter on the beam of the house, and they are very far from one another.
He wrote two letters "al shnei kesalim" - on two different walls.
He wrote two letters "bishnei dapei pinkas" - on two pages of a ledger.
In the last two cases the letters cannot be read together, since they are not close enough to one another to be read as one. In all of these cases he is exempt, because this is not the writing of two letters together in a lasting way.
A single letter that stands for a whole word:
What is the law regarding one who writes a single letter and places a geresh (an apostrophe) beside it, as is very common in Hebrew, to indicate a whole word? For example, one who writes the letter aleph with a geresh, standing for 'adon' (master), or the letter reish with a geresh, standing for 'Rabbi'. He has written two different things, but only one of them is a letter, and the second is nothing more than a geresh.
"Rabbi Yehoshua ben Beseira mechayev" - Rabbi Yehoshua ben Beseira holds him liable, since from that one letter together with that small additional stroke everyone understands a complete word.
"Vachachamim potrin" - and the Sages exempt him, since there still are not two letters here.
In summary: in this mishnah we counted the cases in which the writer is not liable: writing with materials that do not last, or on something that does not last; writing in an unusual manner, with the back of the hand, with the foot, with the mouth and with the elbow; writing that does not amount to two new letters, whether by completing existing writing or by refreshing writing that had been erased, as well as one who intended to write a single letter and wrote two zayins; two letters that are far apart and cannot be read together; and finally the dispute between Rabbi Yehoshua ben Beseira and the Sages concerning a single letter that stands for a whole word.