recur question

(defn run [queue period]
  (loop [log (.takeRaw queue) beg-time -1]
    (cond
     log (let [timestamp (timestamp-of log)]
       (cond (= beg-time -1)
         (when (= (rem timestamp 3600) 0)
           (println log)
           (recur (.takeRaw queue) timestamp))

         (< (- timestamp beg-time) period)
         (do (println log)
             (recur (.takeRaw queue) timestamp))))
     :else (try (Thread/sleep 100)
        (catch InterruptedException ie)))
    (recur (.takeRaw queue) beg-time)))