What does the red mean?

[v0031]

Bob owns a donkey called Tommy. Bob is a very tolerant and kind master. The donkey is lazy and is always finding ways to avoid work.
Once while returning with loads of salt on his back, Tommy falls in the river. He realizes that the weights of the sacks have lessened as part of the salt has dissolved in the water.
The next few days Tommy purposely falls into the water. Bob is unhappy at the way Tommy is behaving because he is losing money in the process. He decides to teach Tommy a lesson.
The next day instead of salt bags he loads Tommy with bags of cotton. Tommy is unaware of the change. As planned, he falls into the water and gets the bags wet. He is very surprised to find the load unbearable. His otherwise master also starts beating him.
Tommy learns his lesson and starts behaving..

[angus]

That is a very chinese story, but it translates nicely into european. 

The version you post is poorly written in terms of antecedents, nevertheless it is clear to me that Bob is the "he" to which is referred in that stanza.  The "otherwise master" is Bob.  The word "otherwise" is unnecessary and confusing.  My guess is that the translator understood just enough English to be dangerous.  Bob was wise to facts other than those to which the ass was privy.  Namely, that the sacks contained payload which wouldn't dissolve in the water and lighten the load.  Read the stanza as though it isn't even there and it makes sense.  Or, if you want to speculate, read it as though it says, "His master, who knew better, also started beating him."

Bob is very clever, by the way.  Far too clever for an Englishman or a Yankee.  I suspect that his real name is Wang or Hu. 

[v0031]

I am not sure where the story is from. But it's not a Chinese one. Maybe from Aesop’s Fables.

[angus]

outstanding!  Yes, I've looked it up and it is one of Aesop's stories.  I suppose I'd forgotten it.  Here's a rough translation into English from the original Klingon:

The Ass Carrying Salt

A certain Huckster who kept an Ass, hearing that Salt was to be had cheap at the sea-side, drove down his Ass thither to buy some. Having loaded the beast as much as he could bear, he was driving him home, when, as they were passing a slippery ledge of rock, the Ass fell into the stream below, and the Salt being melted, the Ass was relieved of his burden, and having gained the bank with ease, pursued his journey onward, light in body and in spirit. The Huckster soon afterwards set off for the sea-shore for some more Salt, and loaded the Ass, if possible, yet more heavily than before. On their return, as they crossed the stream into which he had formerly fallen, the Ass fell down on purpose, and by the dissolving of the Salt, was again released from his load. The Master, provoked at the loss, and thinking how he might cure him of this trick, on his next journey to the coast freighted the beast with a load of sponges. When they arrived at the same stream as before, the Ass was at his old tricks again, and rolled himself into the water; but he found to his cost, as he proceeded homewards, that instead of lightening his burden, he had more than doubled its weight.

The same measures will not suit all circumstances.

There probably weren't many Bobs in Aesop's Greece or Asia Minor (or Klingon for that matter), but in any case this answers your question about Bob.  The beating part isn't mentioned, but the implication that Bob is wise to the fact mentioned in the moral.  (Wise to other stuff, which isn't the same as "otherwise" really.  You should probably mention to your students that it's a faulty translation.)

[True Federalist (진정한 연방 주의자)]

Or an different version, with a critical word left out.  If the words in red were instead "otherwise kind master" the version v posted makes more sense.