midnight
`` In broad daylight , when it ca n't be spotted from the outside , you shall have as much artificial light as you like . If you want to do some writing , that 's the top of the desk on end against the mantlepiece . You 'll never have a better chance so far as interruption goes . But no midnight oil or electricity ! You observe that their last care was to fix up these shutters ; they appear to have taken the top off the desk to get at 'em without standing on it ; but the beastly things would n't go all the way up , and the strip they leave would give us away to the backs of the other houses if we lit up after dark . Mind that telephone ! If you touch the receiver they will know at the exchange that the house is not empty , and I would n't put it past the colonel to have told them exactly how long he was going to be away .