Edwin K Sloat 
Loot of the Void [EPUB ebook] 

Into the Trap-Door City of great spiders goes Penrun after the hidden plunder of the space-pirate Halkon. A century had elapsed since the death of the famous pirate who had preyed on the shipping of the Void with fearless, ruthless audacity and had piled up a fabulous treasure before that fatal day when the massed battle spheres of the Interplanetary Council trapped his ships out near Mercury and blew them to atoms there in the sun-beaten reaches of space.