as clock-work and as inexhaustible as the ocean itself, acts with unfailing constancy, and without the noise, the smoke and the destructive effects of our steam-engines. The tides are nature's own motive power, which she offers to us without stint and free of expense. The Colymbians utilize the generous gift which we neglect for inferior forces that deafen us with their noise, ruin us with their costliness, and destroy us by their ill-regulated action. These tidal machines are gigantic sphygmographs, recording the pulses of the mighty ocean.
There were occasional complaints about the impurity of the air supplied by the air-companies. In some cases it was found that the air-supply was derived from localities which were incapable of furnishing air of perfect purity.
To preserve the purity of the water, there is a very perfect system of what we would call sewerage, the sewage being conveyed to the land, and deposited in various localities appropriated for the purpose, or employed in fertilizing the soil for the growth of cereals. Now it so happened that some of the air-supply companies drew their air from sources where it was apt to be contaminated by the effluvia of the sewage heaps, and Government inspectors and chemists would be appointed to investigate the quality of the air supplied, and the sources whence it was obtained. But, in spite of the unfavourable reports these experts gave, it was a most difficult matter to compel the air-companies, which are great and powerful monopolies, to make the necessary changes in their plant and machinery, in order to secure the necessary purity of their air. The monopolists would resist the orders of the Government to the last, and when at length public opinion
