In chapter six of George Orwell's Animal Farm, we begin to understand just how hard the animals are working to make a go of things on Animal Farm. They are working hard, not only on the regular jobs which must be done on the farm but also to finish the windmill. To make matters worse, Squealer implements a cut in the animals' rations, though of course he couches it as a simple "readjustment" rather than the cut, which it obviously is. The building is a long, slow, laborious process, and without the mighty strength of Boxer, progress would have been virtually impossible. Despite the many hardships, the animals still believe that what they are doing will benefit them and are therefore willing to continue their hard and thankless labor.
Several changes happen on the farm in this chapter. First, Napoleon decides to begin trading with neighboring farms, and Mr. Whymper is now a regular presence on the farm. Even more significant, at least for now, is that the pigs take up residence in the farmhouse, something which was forbidden from the beginning, of course. What we see clearly but what is still hidden from the animals is that the pigs are growing more corrupt and human-like in their behaviors. This is not going to bode well for the animals, but for now things are relatively calm. Hard, but calm.
When November comes, the windmill is nearly half finished, and the animals feel good about their progress. One night there is a terrible storm. Tiles are blown off the roof, chickens are frightened by what sounded like a gunshot, a huge tree is uprooted, and the flagstaff has been knocked over. It was a mighty storm, and when the animals survey the damage, they are horrified to discover that "the windmill was in ruins."
All the animals are dismayed, and even Napoleon moves a little more quickly than usual to see what has happened. He immediately begins sniffing the ground around the base of the windmill, and soon he announces that Snowball is the one who has destroyed the windmill. Here is his claim:
In sheer malignity, thinking to set back our plans and avenge himself for his ignominious expulsion, this traitor has crept here under cover of night and destroyed our work of nearly a year. Comrades, here and now I pronounce the death sentence upon Snowball.
This is an obviously outrageous statement that is not in the least true; however, Napoleon knows he has to blame someone so that no one will blame or turn on him. It takes a little time, but eventually most of the animals reluctantly accept Napoleon's claim. He leads the animals in several ceremonial moments, again in an attempt to distract them and rally the weary animals for the daunting and backbreaking task of rebuilding.
We have seen this tactic before. Both Snowball and Mr. Jones are easy targets to be blamed for anything. They are not there to defend themselves, so they make easy scapegoats for Napoleon and his propaganda-master, Squealer. Asking if the animals want Jones back and making Snowball a common enemy serve to divert any blame or suspicion from the true culprits in the animal's difficult lives.
Snowball had nothing to do with the decimation of the windmill and neither did Napoleon; however, in case the animals decided to rebel against him and to ensure they would rally together to rebuild the windmill, Napoleon falsely blames the innocent Snowball for the act of nature.
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