What is history to ongoing and changing interpretation ?

History is the education of the previous, especially as it is described by written records. The events that occurred before writing was discovered is studied under prehistory. Even though history is studied over and done with written documents, it is open to ongoing and changing interpretations. There are several reasons for this and these are bias, new information, new technology and changes in perception. Some examples are in 1860 which history was almost totally political and by 1900 people were starting to understand that the science of economics added a new layer of interpretation to political history and by 1960 social history had fully emerged. All of this rounds out the representation. 

The townshend duties were repealed, except for the tax on textiles, tea, or glass?

Ibelieve that it is free enterprise as well.