There is no exception under the legislation as you suggest, Tracey :

If the primary reason for keeping the horses was to work on the farm, and your and LauraG's posts below imply that was very important work, then the horses were not being kept for amusement but for work.

There was no exception under the legislation as to the amount of use for which a farm horse may also be used as a carraige horse.

The tax was applied to one or the other , not a combination of both.

Your "primary reason" for the use of the horse argument was not allowed under the legislation.

It is logical , if you consider it carefully.

If you owned horses which quailfed for taxation under both heads- pleasure/carriage horses and also for agricutural useage-,why would you be allowed to escape the higher taxes and to use horses for "pleasure " purposes simply because you are also using them for agriculture?

There is nothing in the legislation I can see which allows occasional use as carraige horses to be used as an excuse by the owner for not paying the full rate of tax.

If your horses qualified to be taxed under the higher usage rate( for carraige/pleasure) then you would pay that rate,( but only if you had honestly declared it to the local excise man)