The best guarantee against invasion would be, complete naval supremacy on the lakes and rivers, because they constitute the most accessible roads for the invaders, and the most serviceable barriers for defenders if they have the proper means of defence. To give any chance of successful resistance, some equality of naval force on the part of the invaded is almost indispensable. The question arises, who shall provide this naval force? Canada cannot. She is prevented by Imperial treaties, by want of means, and even if she had them, she is forbidden to use the means, by the principle which forbids a dependency equipping ships of war in times of peace. Great Britain has no doubt a powerful fleet, but the far inferior navy of the United States, close at hand, contains more vessels suitable for warlike operations in inland waters and canals than we possess, 4000 miles away. In fact we ought to have a very great preponderance of small vessels to give us a fair start, and even then it would be difficult to begin hostilities on equal terms. Lake Michigan, with the enormous resources of Chicago, is entirely American, and the possession of such a base is an advantage which is by no means counterbalanced by our position on Lake Huron. To prevent the enemy clearing all before them on the lakes, by an energetic naval sortie from their ports, it would be necessary to have the means of furnishing a flotilla as soon as hostilities became imminent, and to watch every point, particularly such as that of Sorel, where communication from Richelieu to the St. Lawrence might be interrupted. But it is thought we cannot hope to cope with the Americans on equal terms in all the lakes, and that we must be content with concentrating our strength on Lake Ontario and in the St. Lawrence. All our water-ways are very much exposed. Whilst Great Britain retains her supremacy, the St. Lawrence is open during the summer, and can be kept free by iron-plated vessels as far up as Montreal. The day of wooden gunboats has passed, and it becomes requisite for the Government to take immediate steps to secure an adequate supply of armoured vessels on the spot as soon as hostilities become probable. It is gratifying to know that the Canadian Legislature is about to fortify the harbour and arsenal at Kingston, so as to cover the infant naval force. Under any circumstances, it is not possible to defend a canal by guarding the locks, or by placing forts at particular places, and yet the canals are of vital importance to us. The Beauharnais Canal runs on the right bank of the St. Lawrence, and is peculiarly unfortunate in its military position. The Welland Canal is of consequence, but it would be better to destroy it than permit an enemy to hold it. The Rideau Canal, which runs from Lake Huron to Kingston, is a very valuable communication, but it needs to be deepened and enlarged at the Rapids. All the canals require to be enlarged and improved, but they are far better