During his last period of liberty in 1870, Bollert followed the profession of burglary and swindling on a large scale. The scene of his activity extended from Munich to the Rhine. He was clever at disguises and used a variety of costumes, wearing false beards of different hues; he possessed the complete uniform of a Bavarian railway guard, in which he once got as far as Bingen without a ticket. He plied his nefarious trade in Frankfurt, Würzburg, Heidelberg, Darmstadt, Nürnberg and Augsberg. At hotels he managed by means of false keys to enter the rooms of people who were absent, and often carried away all the articles of value he could lay hands on. In Frankfurt he was once arrested, but succeeded in breaking out of the prison. In Würzburg he was again caught and here the Court of the Assizes sentenced him to thirteen years’ penal servitude. No one would have taken Bollert for a dangerous and bold burglar. In spite of his fifty-one years, he presented a handsome appearance, had a great charm of manner and looked well even in a convict’s dress. His expression was gentle, his address was civil and conciliating, but not in the least cringing; his bearing toward the officials was never too submissive, but always polite. Ladies, whose feet he measured in his capacity of chief shoemaker, were never tired of describing the elegant manner in which he bowed, and they took a great interest in the history of this attractive convict. He was entrusted with the purchase of all the leather required by the board of management of the prison, and not only acquitted himself of this task to their entire satisfaction, but also cut out the most perfect shoes the officials’ wives had ever worn. He was a Catholic and soon became an acolyte, serving the mass with a fervour never before manifested by a convict in prison. In his intercourse with the other prisoners he was always reserved, and he was and remained the “gentleman”--they always spoke of him as “Herr” Bollert. He never descended to frauds or low tricks, he never betrayed any one; but openly expressed his contempt for the behaviour of many of his companions in misfortune, without their daring to resent it. If he was offered a glass of wine or beer in the house of one of the officials, he never mentioned the circumstance. How was it that a man capable of thus altering his conduct, one may say his whole character, for a series of years, fell back into the old vicious course of action, upon being freed from restraint?