The enviroment is actually quite simple. Actually, not many physical enviroments except for the farm is described at all. The main focus of the book is the different personalities and how they change and interact with eachother when the animals form a society. Because of this, the physical enviroment isn't really relevant and therefore isn't really described. Of course there is some places that are mentioned. For example there is the different houses of the farm like the barn and the farm house. But other than that there isn't alot of physical enviroments that are mentioned. It feels as if the enviroment doesn't really matter anyways since the whole book is pretty metaphorical and because the enviroment doesn't really affect the social conflicts that can occur while forming a society. Most of the information that you get about the enviroment have to be concluded by the reader from certain actions and behaviours. For example there is this event at a really early stage of the book where the animals just took over the farm that indicates that there is fences around the farm. "Napoleon sent for pots of black  and  white paint  and led the way down  to the five−barred gate that gave
on  to the main road."(Animal Farm, George Orwell, page 8)
Since there is a gate, there is obviously also a fence.

The weather in the enviroment constantly changes. One chapter it might be summer, and during the next it might be cold winther. This is because the book is written over a large time span.

Even though the author doesn't really describe the physical enviroment alot, there is a social enviroment that is very clearly illustrated by the autor. At the start of the book the social enviroment is very friendly and democratic. However, after a few chapters the society changes and the enviroment becomes very tense and strict since sort of a dictature forms. This is very clear when Napoleon takes on the role as the leader of the society and uses his well trained dogs to make people scared of disagreeing with him.

Some of the pigs  themselves, however,
were more articulate.  Four  young porkers in the  front row uttered shrill  squeals of disapproval,  and all four of
them  sprang to  their feet and began speaking at  once.  But  suddenly the  dogs sitting round Napoleon let out
deep, menacing growls, and  the  pigs  fell silent  and sat down again. (Animal farm, George Orwell, page 17)

Even though the writer doesn't describe the enviroment directly alot, i can still envision it. This is because all of the subtle actions and behaviours that indicates a certain enviroment. The small things like the gate that indicated a fence in the first quote all comes together after a few chapters and therefore i can envision the enviroment even though the writer doesn't write it out.

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