"Wait one moment, Mr. Martin," called up Bart sharply. "This is a special delivery, and a very important matter. I tender you this package in the presence of these witnesses, and it is a legal delivery. If you decline to come down and take it, and I leave it on your doorstep at the call of the first tramp who happens to come along, I have done my duty, and the loss is yours--a matter of fifteen thousand dollars."