Magnetical Investigations

Part I: 1. Introductory observations; 2. Description of ready and effective processes for magnetizing large bars and thin plates; 3. The ready determination of the proportional directive powers of magnetic needles or bars; 4. The determination of the relative strength or tenaciousness of the magnetic condition; 5. The determination of the ratio of the power of magnets; 6. The determination of the relative degree of hardness or temper; 7. The determination of the quality of bars, plates, or instruments constructed of steel; 8. Inferences, from these investigations; Part II: 1. As to the powers of combinations of magnetized plates of tempered steel in contact; 2. On the powers of combinations of magnetized steel plates separated by limited spaces; 3. On the relative powers of combinations of magnetized steel plates or bars; 4. On the relative powers, in combination or separately, of hard plates or bars of steel; 5. On the magnetical powers of steel plates; 6. On the effects of the annealing of hard steel plates; 7. On the powers of hard steel bars combined in various ways; 8. Of the magnetical powers, receptive and permanent, of cast iron; 9. On the measure of permanency of the energy in straight-bar magnets.