I was thinking the other day, that the peak power of my car is 140bhp, which is theoretically (or more, historically) broadly equivalent to the power that 140 horses would provide, if all working optimally and together.
But even if 140 horses were to work together to pull, let's say, some form of cart, would the power really be all that useable? Would the horses not just end up bumping in to each other?
Let's take this a step further - let's say the 140 horses were all arranged in some sort of formation, with some form of framework, that prevented them from accidentally running into each other, and just for argument's sake let's say this framework doesn't weight anything (which of course it would, but this is just theoretical). The horses at the front would not only be pulling along the weight of the cart, but also the weight of the other horses, plus their own weight.
So one horse power in actual terms is the same in terms of power, but a horse must surely weigh something - I'm guessing around 200-250kg (complete guess), so the power to weight ratio of a horse really isn't all that impressive, and the power to weight ratio of, say, 140 horses all working together (not taking into account the framework type device), would be actually quite abysmal.
But I suppose it's a measure we're all familiar with, and that's what counts.
Peter