But sure as are the wasting inroads of time and the climate, St Petersburg is in daily peril of an overthrow whose accomplishment would require but a few hours. The Gulf of Finland forms a vast funnel pointing eastward, at the extremity of which stands the city. No portion of the city is fifteen feet above the ordinary level of the water. A strong westerly wind, blowing directly into the mouth of the funnel, piles the water up so as to lay the lower part of the city under water. Water is as much dreaded here, and as many precautions are taken against it, as in the case of fire in other cities. In other cities alarm-signals announce a conflagration; here they give notice of an inundation. The firing of an alarm-gun from the Admiralty, at intervals of an hour, denotes that the lower extremes of the islands are under water, when flags are hung out from the steeples to give warning of danger. When the water reaches the streets, alarm-guns are fired every quarter of an hour. As the water rises the alarms grow more and more frequent, until minute-guns summon boats to the assistance of the drowning population. So much for the lower jaw of the monster that lies in wait for the Russian capital; now for the upper:—Lake Ladoga, which discharges its waters through the Neva, is frozen over to an enormous thickness during the long winter. The rapid northern spring raises its waters and loosens the ice simultaneously; when the waters of the Gulf are at their usual level, the accumulated ice and water find an easy outlet down the broad and rapid Neva. But let a strong west wind heap up the waters of the Gulf just as the breaking up of Lake Ladoga takes place, and the waters from above and from below would suffice to inundate the whole city, while all its palaces, monuments, and temples would be crushed between the masses of ice, like “Captain Ahab’s” boat in the ivory jaws of “Moby Dick.” Nothing is more probable than such a coincidence. It often blows from the west for days together in the spring; and it is almost a matter of certainty that the ice will break up between the middle and the end of April. Let but a westerly storm arise on the fatal day of that brief fortnight, and farewell to the City of the Czars. Any steamer that bridges the Atlantic may be freighted with the tidings that St. Petersburg has sunk deeper than plummet can sound in the Finnish marshes from which it has so magically risen. [Illustration.] The Inundation of 1824.