# What letter-counting system was used to mark the Planks of the Mishkan?

The sides between the 48 Planks of the Mishkan were marked with letters to keep them in order during assembly/disassembly (Shabbos 103a, & here). If the pairing system was one-letter:one-letter, then using the alef-bet would fall 25 spaces short.

א:א, ב:ב, ג:ג, ד:ד – ת:ת (finite set of 22)

So how did they number the Planks?

I'm still hoping someone has a sourced answer, but I came up with a possible answer last night - reverse order.

I was learning Shabbos 104a, where the Gemara gives a really nice explaination of the meaning behind the order/shape of the letters in the alef-bet, and how it reflects the actions and reward of a Tzadik. Since the luchot could be read from both the front and back, after reaching ת, the Gemara gives the meaning of the Atbash of the alef-bet, and how it's an exegesis for Rashas.

Since the planks have rings only on one side, using reverse-order, there can be both a right and left set of Planks. Each set would be distinguishable by whether the alef-bet is going forward or backwards as you look at it from the ring-side. This would still leave me 3 spaces short though (47 spaces, 44 letters).

The solution I came up with is to not label the two corner planks, since they were unique and their placement was obvious (like the corner pieces of a puzzle). And have one Tav shared between both sets.

or msh210's comment:

• @zq Genious. It would definitley solve all the problems, and makes plenty of sense. BTW, why no use of the final letters? – avi Nov 24 '11 at 13:53
• @avi, I left out the final letters for two reasons. First, they don't fit as nicely, using the alef-bet twice would result in more letters than spaces. And second, I wanted to allow for paleo-hebrew, which didn't have final letters. – zaq Nov 24 '11 at 15:55

From Rashi to Shabat 73:1 on the Mishna: ".. and writes one letter in one (plank) and another one in the adjacent". From here we learn that there was only 1 letter in each one. But the letters were written in pairs (one for each plank) that's the reason why the melacha speaks of 2 letters. א-א, ב-ב, ג-ג...

Although I didn't find a source for it but the problem that Zaq brought in his question could be easily solved by using different heights (High, Middle and Low).

אא:אא, אב:אב, אג:אג, אד:אד – את:את

This is why the halacha for writing requires 2 letters.

• I thought in your comment that I cited, you were saying it was a one-letter system. Did I completely misunderstand? – zaq Nov 22 '11 at 17:49
• Is there a connection to the Achas, Achas V’achas, Achas U’shtaim counting on Yom Kippur? – zaq Nov 22 '11 at 19:23
• Could also be that they indeed started with א:א, ב:ב, etc., and then when they ran out of single letters went to double ones (אא:אא, אב:אב, etc.). That would still explain why the melachah is two letters at minimum, because for some of the pairs of planks (the first 22) that's all they needed. – Alex Nov 22 '11 at 20:55
• @zaq no I contradicted myself – avi Nov 22 '11 at 21:03
• @zaq - That funny counting method was to keep it clear in the kohen's mind which sprinkling he was up to. There were 8 all together - one set of one and one set of seven. If he just counted from one to eight he might think he is counting the set of seven and get confused, while if he just counted to one and started over again counting to seven he might think he was counting them all together and go up to eight. I don't think that risk was at play in the case of the k'rashim since they didn't need to actually count them, just ensure they were in the right places – WAF Nov 24 '11 at 14:47