"Better keep as far from the Bulgarians as possible," he said in a harsh voice. "I know something of the Bulgarians."
Hal nodded.
"Besides, we have other business," he added. "We do not want to fall into the hands of the Bulgarians if we can possibly help it. We have a mission to perform if it is humanly possible."
"Boom!" it was the sound of a big gun.
"The battle is on," said Hal. "Will any of you come to the roof with me?
We should be able to get a good view."
"Boom! Boom! Boom! Boom! Boom!"
The battle was on in full blast.
CHAPTER XXVI.
IN GRAVE PERIL.
Helen led the way to the roof, the others following closely. As Hal had predicted, it was possible from this height to obtain a fair view of the opposing armies.