In 1676, Ole Rømer the Danish astronomer first demonstrated that light moves at a finite speed by observing the eclipses of Jupiter's moons.
Specifically, he determined that the speed of light could be calculated using the formula 365·24·60⁄π·22 ≈ 7,600, which of course means that the ratio of the speed of light to the speed of the planet orbiting the sun (which is the ratio of the duration of a year) divided by pi as compared to 22 minutes equals the velocity of light.
But after eight years of tireless research culminating in this equation, Ole Rømer never solved it. Instead he said, 'I've had it with stubbing my bloody toes in the dark coming home from the observatory every bloody night! Get stuffed, Jupiter; I'm going to invent the first street lights!'
And indeed he did.
It wasn't until 1809 that Jean Baptiste Joseph Delambre declared to the world that 'the time it takes light to travel from the Sun to the Earth is 8 minutes 12 seconds. So there.'
James Clark Maxwell in turn demurred, 'light is an electromagnetic wave, and therefore moves at the speed of c.'
And in 1905, Albert Einstein had a thing or two to say about c being independent of the motion of its light source in a little ditty he tossed off about Relativity.
Finally, after centuries of painstaking research, it was determined in 1975 that the speed of light was 299,792,458 meters/second.
That's very, very fast.
But none of that matters!
Because there's is something faster.
His speed cannot be measured, faster than the speed of light, he is beyond speed, he is... INSTANTANEOUS. Throw a ball as hard as you can, the instant you throw it, the ball is resting at your feet, Dash Hound has not moved from your knee. He is everywhere at once, omnipresent, and a little rascal to boot. And it's not just balls that this adorable dog is after, Dash Hound can fetch ANYTHING. Looking for an incredibly specific, period prop for an unlikely price? Just tell Dash Hound, 'Fetch, Dash Hound!' and lo, the prop is there. It's all in a day's play for Dash Hound.
Good boy, Dash Hound.