There was a pneumatic-tube postal system delivering mail between Brooklyn and Manhattan in the years right before and after 1900, though efforts to make considerable expansions to the service met with resistance. An article from the May 21, 1902 Brooklyn Daily Eagle:

The Pneumatic Tube Postal Commission has apparently concluded that it is not worth while to extend the pneumatic service in this borough beyond the former limits. This is not because the commission thinks badly of the propositions recently submitted by Postmaster Roberts. With these there could have been no reasonable ground for quarrel. Had it been possible to carry them out in their entirety the result would have been of great benefit to Brooklyn in improving the postal service of the borough by connecting the main office with outlying stations with which communication is at present not nearly so expeditious as it might be. But the law authorizing the making of contracts with the tube companies stood in the way of Mr. Roberts’ plan with a provision that not more than 4 per cent of the postal revenues of a city shall be used for the installation of a pneumatic service. After the Brooklyn and New York offices have been joined together, as they were a few years ago, the commission estimates that not more than $60,000 will be available for the extensions asked by Postmaster Roberts. At an estimated maximum cost of  $17,000 per mile this expenditure would give to Brooklyn something more than three miles of local extensions, but the commission is inclined to consider that in this case half a loaf is worse than no bread, and will therefore decline to authorize the extensions until such time as more money is made available.

There is no doubt that the postal service of Brooklyn would be materially improved even by the expenditure of so small a sum as $60,000. Why wait until more money is available? Why not extend as far as possible with what funds are at hand and trust to the future for the complete realization of plans that for the present must be either mollified or abandoned altogether? If we cannot get what we ought to have by all means let us have what we can get.•