Time is not the fourth dimension.
Being three dimensional creatures, we can not perceive the 4th dimension. We can however, infer what a 4th dimensional object would look like basis its effect on our 3-dimentional universe.
To make things simple at first, imagine how a three dimensional object would interact with a two dimensional universe. Push a ball through a plane. At the time when ball first makes contact with the 2nd dimension, it appears as a single point to the 2-dimensional creatures which inhabit that universe. As we continue to push the ball through the plane, a circle forms out of the point and continues to expand up to the maximum diameter of the ball. As we continue, the circle begins to shrink back to a single point and then disappear completely when the ball has left the plane. To us 3rd dimensional people, the ball still exists next to the plane, but the poor 2nd dimensional creatures can no longer detect it because it is no longer in their universe.
Now imagine a 4th dimensional ?ball? is pushed through our universe. It would start as a point, grow into a ball with a maximum diameter equal to the diameter of the 4th dimensional ?ball,? shrink down to a single point, and finally disappear from our universe.
That is the fourth dimension.
Time sensed the same regardless if you were a 1st, 2nd, 3rd, or 4th dimensional creature. It would still take X seconds to travel between two points at a given velocity.
Up next, 'What really caused the big bang.'