The animals are proud and confident after their victory in the Battle of the Cowshed. They lose one of their own, however, when Mollie disappears, only to be seen by the pigeons pulling a cart on another farm. The winter is a cold one, and the rivalry between Snowball and Napoleon becomes more bitter. Their main debate is over Snowball's proposal to build a windmill, which will provide power, comfort and less work for the animals. Napoleon opposes the construction, calling Snowball's plan for modern equipment "nonsense." Snowball gives an emotional speech on the day of the vote to decide the leader of Animal Farm, but the vote is never taken. Napoleon sends nine vicious dogs--the puppies he has been nurturing--and they run Snowball off the farm. Napoleon announces that a committee of pigs will run the farm, and the dogs put an end to any possible dissent. Later, Napoleon declares that the windmill will be built after all, that it was his idea in the first place, and that he had never opposed it.
Winter is approaching. Mollie, who has been avoiding work more and more, is found to have been accepting gifts of ribbon and sugar from one of the men on the neighbouring farm. Shortly afterwards she disappears, and is said to be pulling a cart in the town. No one on the farm ever sees her again, and she is never mentioned again.
With the land now frozen solid, it is impossible to do any farming. A lot of time is spent on meetings of all the animals in the big barn, where the future policy for the farm is discussed and voted on. The divisions between Snowball and Napoleon are becoming more pronounced, and it seems that they now oppose each other on every proposal. Snowball’s eloquence allows him to control the meetings, However, Napoleon works quietly behind the scenes building support, and succeeding in getting all of the sheep onto his side.
Snowball is forever proposing new plans and schemes for the improvement of the farm, all of which are opposed by Napoleon. Snowball’s most ambitious plan is for the construction of a windmill, which he says can provide heat and electricity to the farm. He accepts that it will be a huge undertaking, and is vague about some of the details. Napoleon is completely against the idea, and makes his opposition clear. Snowball continues to work on his plans, and spends hours every day in a shed working on them, drawing them out on the wooden floor. All of the animals visit Snowball regularly in the shed to watch the plans grow into something that looks very complex and impressive. Only Napoleon holds back, and when he does come to inspect the plans, he urinates on them.
The day comes when all the animals will gather in the big barn to vote on whether or not the windmill will be built. The farm is divided into two factions at this stage, the “Vote for Snowball and the three-day week” faction, and the “Vote for Napoleon and the full manger” faction. Snowball has convinced his faction that the windmill will lead to increased leisure time for everybody, while Napoleon has convinced his faction that the distraction of the windmill will cause the animals to lose time on the harvest and starve.
The meeting begins. The sheep heckle Snowball as he explains his plans for the windmill, and why it will be good for the farm. Napoleon then rises and gives a very brief and curt address, advising everyone to vote against the windmill. Snowball then speaks again. He talks passionately and eloquently, and creates a vision of a mechanised farm with heat and light, with electrical threshers and ploughs and reapers, where the animals do little or no work, and All the labour is carried out by the electricity generated by the windmill. It is clear that Snowball will win the vote.
Just then, Napoleon stands and emits a queer sound, a kind of whimper. At this signal, nine huge dogs, the dogs that Napoleon took away as puppies months before, rush into the barn and charge at Snowball. They chase him from the barn and off the farm. He is never seen again.The other animals, who had left the barn to watch the chase, now return to the barn, where Napoleon addresses them. He tells them that Sunday Meetings are henceforth abolished, and that all decisions in future will be taken solely by the pigs. Any dissent is silenced by growls from the dogs, and the meeting finishes to a fifteen-minute chorus of “Four legs good, two legs bad” from the sheep.