James Gregory, in his Optica Promota (1663), discusses the forms of images and objects produced by lenses and mirrors, and shows that when the surfaces of the lenses or mirrors are portions of spheres the images are curves concave towards the objective, but if the curves of the surfaces are conic sections the spherical aberration is corrected.
But these two sections of Protestantism, in their common exile and in presence of the preponderating Roman Catholicism of the country, seemed at first inclined to draw closer together than had been thought possible in Great Britain.
The recovery of its concluding sections in the same MS. which brought the Didache to light, proves beyond question that we have here the earliest extant sermon preached before a Christian congregation, about A.D.
There was no impact in Wohler's experiments, and therefore it would seem rational to add the impact allowance to that for fatigue; but in that case the bridge sections become larger than experience shows to be necessary.
Considering however the two sections of the Passover separately, it is remarkable how many of the ceremonies associated either historically or ceremonially with the Passover have connexion with the idea of a covenant.
The three great sections of aerial, terrestrial, and aquatic birds are abolished.
The cork is thereafter removed in the sections into which it has been cut, by inserting under it the wedge-shaped handle of the implement used in making the incisions.
See Plans, Elevations, Sections and Details of the Alhambra; from drawings taken on the spot by J.
Marquart edits with commentary under the title Eransahr the sections of the geography relating to Persia).
Experiments on alloys are, in some ways, easier to make than on pairs of non-metallic substances, partly owing to the possibility of polishing sections for microscopic examination, and the investigation of alloys has done much to elucidate the general phenomena of solution, of which metallic solution constitutes a special case.