Why did Montmorency look at the boiling kettle with hatred?

The kettle hissed and spit, thus, arousing Montmorency's curiosity. He'd growl at it to no avail, and when he finally got a hold of it was taught a lesson he wouldn't soon forget. The tea-kettle fought back and won.

It was only a little kettle, but it was full of pluck, and it up and spit at him.

“Ah! would ye!” growled Montmorency, showing his teeth; “I’ll teach ye to cheek a hard-working, respectable dog; ye miserable, long-nosed, dirty-looking scoundrel, ye. Come on!” And he rushed at that poor little kettle, and seized it by the spout.

Then, across the evening stillness, broke a blood-curdling yelp, and Montmorency left the boat, and did a constitutional three times round the island at the rate of thirty-five miles an hour, stopping every now and then to bury his nose in a bit of cool mud.