Many of the coal shippers of Richmond, Va., have been, and are, exporting coal to Havana, and other tropical climates, packed in large hogsheads, which, upon their arrival at the destined ports, are emptied, filled with sugar and molasses, and re-exported to the United States. This is a new idea, and causes a 'vast saving to both manufacturers and consumers, as formerly it was the custom to export the staves and hoops, and have the hogsheads put together on the plantations, where coopers' wages are much higher than here; saving in that and likewise in the transportation, which has generally been considered an important item in our commerce. A Crystal Palace project is in agitation at Boston.