Typo fix, s/pubic/public/

ch05.asciidoc

@@ -23,7 +23,7 @@ In some ways it helps to think of a transaction in the same way as a paper chequ
 
 Transactions can be created online or offline by anyone, even if the person creating the transaction is not an authorized signer on the account. For example an accounts payable clerk might process payable cheques for signature by the CEO. Similarly, an accounts payable clerk can create bitcoin transactions and then have the CEO apply digital signatures to make them valid. While a cheque references a specific account as the source of the funds, a bitcoin transaction references a specific previous transaction as its source, rather than an account. 
 
-Once a transaction has been created, it is signed by the owner (or owners) of the source funds. If it was properly formed and signed, the signed transaction is now valid and contains all the information needed to execute the transfer of funds. Finally, the valid transaction has to reach the bitcoin network so that it can be propagated until it reaches a miner for inclusion in the pubic ledger, the blockchain.
+Once a transaction has been created, it is signed by the owner (or owners) of the source funds. If it was properly formed and signed, the signed transaction is now valid and contains all the information needed to execute the transfer of funds. Finally, the valid transaction has to reach the bitcoin network so that it can be propagated until it reaches a miner for inclusion in the public ledger, the blockchain.
 
 [[tx_bcast]]
 ==== Broadcasting Transactions to the Bitcoin Network