Cipher and secret letter and telegraph code, with Hogg's improvements. The most perfect code ever invented or discovered. Impossible to read without the key. Invaluable for secret, military, naval, and diplomatic services, as well for brokers, bankers, an

Cipher and secret letter and telegraph code, with Hogg's improvements. The most perfect code ever invented or discovered. Impossible to read without the key. Invaluable for secret, military, naval, and diplomatic services, as well for brokers, bankers, an