Strangeness with times

I am trying to copy a cell containing a time to another using .value but this results in a decimal!

Try running this on your computer:

Cells(1, 1).Value = "18:00"
Cells(1, 2).Value = Cells(1, 1).Value

On the first cell, the value is 18:00 all right, but the second cell is 0.75! (=18/24 perhaps?)

Can anybody explain why this happens? Is there is a way to copy the time correctly?

I know that a copy-and-paste will get round this, but do not want to it because it will transfer all the formatting from my source cell to my target cell.

Many thanks,

Andrew