And Engineer Serko describes enthusiastically the various advantages of the new explosive which, he says, is incontestably superior to any yet invented.
"And what a destructive effect it has," he adds. "It is analogous to that of the Zalinski shell, but is a hundred times more powerful, and requires no machine for firing it, as it flies through the air on its own wings, so to speak."
I listen in the hope that Engineer Serko will give away a part of the secret, but in vain. He is careful not to say more than he wants to.
"Has Thomas Roch," I ask, "made you acquainted with the composition of his explosive?"
"Yes, Mr. Hart--if it is all the same to you--and we shall shortly have considerable quantities of it stored in a safe place."
"But will there not be a great and ever-impending dange
