He organised extensive magnetical and meteorological observations, and in 1839 he started regular observations of the periodical phenomena of vegetation, especially the flowering of plants.
The magnetical needle, and its suspension on a stick or straw in water, are clearly described in La Bible Guiot, a poem probably of the r3th century, by Guiot de Provins, wherein we are told that through the magnet (la manette or l'amaniere), an ugly brown stone to which iron turns of its own accord, mariners possess an art that cannot fail them.
Barlowe, in his treatise Magnetical Advertisements, printed in 1616 (p. 66), complains that "the Compasse needle, being the most admirable and usefull instrument of the whole world, is both amongst ours and other nations for the most part, so bungerly and absurdly contrived, as nothing more."
This work, which embodied the results of many years' research, was distinguished by its strict adherence to the scientific method of investigation by experiment, and by the originality of its matter, containing, as it does, an account of the author's experiments on magnets and magnetical bodies and on electrical attractions, and also his great conception that the earth is nothing but a large magnet, and that it is this which explains, not only the direction of the magnetic needle north and south, but also the variation and dipping or inclination of the needle.
Identity and difference among ideas, as when we say that " blue is not yellow "; or (b) with mathematical relations, as that " two triangles upon equal bases between two parallels must be equal "; or (c) in assertions that one quality does or does not coexist with another in the same substance, as that " iron is susceptible of magnetical impressions, or that ice is not hot "; or (d) with ontological reality, independent of our perceptions, as that " God exists " or " I exist " or " the universe exists."