[Sidenote: November, B.C. 64.] Well might Cicero be alarmed at such a combination; well might he say that if a generation of such youths lived to manhood there would be a commonwealth of Catilines. But what was to be thought of the prospects of a society in which such phenomena were developing themselves? Cicero bade them all go--follow their chief into the war, and perish in the snow of the Apennines. But how if they would not go? How if from the soil of Rome, under the rule of his friends the Senate, fresh crops of such youths would rise perennially? The Commonwealth needed more drastic medicine than eloquent exhortations, however true the picture might be. [Sidenote: November, B.C. 63.] None of the promising young gentlemen took Cicero's advice. Catiline went alone and joined Manlius, and had he come on at once he might perhaps have taken Rome. The army was to support an insurrection, and the insurrection was to support the army. Catiline waited for a signal from his friends in the city, and Lentulus, Cethegus, Autronius, and the rest of the leaders waited for Catiline to arrive. Conspirators never think that they have taken precautions enough or have gained allies enough; and in endeavoring to secure fresh support they made a fatal mistake. An embassy of Allobroges was in the city, a frontier tribe on the borders of the Roman province in Gaul, who were allies of Rome, though not as yet subjects. The Gauls were the one foreign nation whom the Romans really feared. The passes of the Alps alone protected Italy from the hordes of German or Gallic barbarians, whose numbers being unknown were supposed to be exhaustless. Middle-aged men could still remember the panic at the invasion of the Cimbri and Teutons, and it was the chief pride of the democrats that the State had then been saved by their own Marius. At the critical moment it was discovered that the conspirators had entered into a correspondence with these Allobroges, and had actually proposed to them to make a fresh inroad over the Alps. The suspicion of such an intention at once alienated from Catiline the respectable part of the democratic party. The fact of the communication was betrayed to Cicero. He intercepted the letters; he produced them in the Senate with the seals unbroken, that no suspicion might rest upon himself. Lentulus and Cethegus were sent for, and could not deny their hands. The letters were then opened and read, and no shadow of uncertainty any longer remained that they had really designed to bring in an army of Gauls. Such of the conspirators as were known and were still within reach were instantly seized.