Page images
PDF

tion,-the eye having been completed in all but the formation of the lens,—the place which the lens occupies when completed, was filled with parts of the humors and plane membrane, homogeneous in texture and surface, presenting, therefore, neither the variety of the materials, nor forms which are contained in the optician's shop for chance to make its combinations with. . How then could it be cast of a combination not before used, and fashioned to a shape different from that before known, and placed in exact combination with all the parts before enumerated, with many others not even mentioned? He sees no parallelism of condition then, by which chance could act in forming a crystalline lens, which answers to the condition of an optician's shop, where it might be possible in many ages for chance to combine existing forms into an achromatic object-glass. Considering, therefore, the eye thus completed and placed in in its bony case and provided with its muscles, its lids, its tearducts, and all its other elaborate and curious appendages, and, a thousand times more wonderful still, without being encumbered with a single Superfluous or useless part, can he say that this could be the work of chance? The improbability of this is so great, and consequently the evidence of design is so strong, that he is about to seal his verdict in favor of design when he opens Mr. Darwin's book. . There he finds that an eye is no more than a vital aggregation or growth, directed, not by design nor chance, but moulded by natural variation and natural selection, through which it must, necessarily, have been developed and formed. Particles or atoms being aggregated by the blind powers of life, moist become under the given conditions, by natural variation and natural selection, eyes, without design, as certainly as the red billiard ball went to the west pocket, by the powers of inertia and elasticity, without the design of the hand that put in motion. (See Darwin, . 169. p Let * lay before our skeptic the way in which we may suppose that Darwin would trace the operation of life, or the vital force conforming to these laws. In doing this we need not go through with the formation of the several membranes, humors, &c., but take the crystalline lens as the most curious and nicely arranged and adapted of all the parts, and as giving moreover a close parallel, in the end produced, to that produced by design, by a human designer, Dollond, informing his achromatic object. glass. If it can be shown that natural variation and natural selection were capable of forming the crystalline lens, it will not be denied that they were capable of forming the iris, the sclerotica, the aqueous humors, or any and all the other parts. Suppose, then, that we have a number of animals, with eyes yet wanting the crystalline. In this state the animals can see, but dimly and imperfectly, as a man sees after having been couched. Some of the offspring of these animals have, by natural variation, merely, a portion of the membrane which separates the aqueous from the vitreous humor, a little thickened in its middle part, a little swelled out. This refracts the light a little more than it would be refracted by a membrane in which no such swelling existed, and not only so, but in combination with the humors, it corrects the errors of dispersion and makes the image somewhat more colorless. All the young animals that have this swelled membrane see more distinctly than their parents or brethren. They, therefore, have an advantage over them in the struggle for life. They can obtain food more easily; can find their prey, and escape from their enemies with greater facility than their kindred. This thickening and rounding of the membrane goes on from generation to generation by natural variation; natural selection all the while “picking out with unerring skill all the improvements, through countless generations,” until at length it is found that the membrane has become a perfect crystalline lens. Now where is the design in all this? The membrane was not thickened and rounded to the end that the image should be more distinct and colorless; but, being thickened and rounded by the operation of natural variation, inherent in generation, natural selection of necessity produced the result that we have seen. The same result was thus produced of necessity, in the eye, that Dollond came at, in the telescope, with design, through painful guessing, reasoning, experimenting, and formIng. Suppose our skeptic to believe in all this power of natural selection; will he now seal up his verdict for design, with the same confidence that he would before he heard of Darwin 2 If not, then “the supposed proof from design is invalidated by Darwin's theory.” - .

SECOND READER.—Waiving incidental points and looking only to the gist of the question, I remark that, the argument for design as against chance in the formation of the eye, is most convincingly stated by you on p. 235-237. Upon this and numerous similar arguments the whole question we are arguing turns. So, if the skeptic was about to seal his verdict in favor of design, and a designer, when Darwin's book appeared, why should his verdict now be changed or withheld 2 All the facts about the eye, which convinced him that the organ was designed, remain just as they were. His conviction was not produced through testimony or eye-witness, but design was irresistibly inferred from the evidence of contrivance in the eye itself. -

Now, if the eye as it is, or has become, so convincingly argued design, why not each particular step or part of this result?

If the production of a perfect crystalline lens in the eye—you know not how, as much indicated design, as did the production of a Dollond achromatic lens,—you understand how—then why does not “the swelling out” of a particular portion of the membrane behind the iris—caused you know not how—which, by “correcting the errors of dispersion and making the image somewhat more colorless,” enabled the “young animals to see more distinctly than their parents or brethren,” equally indicate design —if not as much as a perfect crystalline, or a Dollond compound lens, yet as much as a common spectacle glass? / Darwin only assures you that what you may have thought | was done directly and at once, was done indirectly and success| ively. But you freely admit that indirection and succession do not invalidate design, and also that Paley and all the natural theologians drew the arguments which convinced your skeptic wholly from eyes indirectly or naturally produced. Recall a woman of a past generation and show her a web of cloth; ask her how it was made, and she will say that the wool or cotton was carded, spun, and woven by hand. When you tell her it was not made by manual labor, that probably no hand has touched the materials throughout the process, it is possible that she might at first regard your statement as tantamount to the assertion that the cloth was made without design. If she did, she would not credit your statement. If you patiently explained to her the theory of carding machines, spinning jennys, and powerlooms, would her reception of your explanation weaken her conviction that the cloth was the result of design? It is certain that she would believe in design as firmly as before, and that this belief would be attended by a higher conception and reverent admiration of a wisdom, skill, and power so greatly beyond any thing she had previously conceived possible. Wherefore, we may insist that, for all that yet appears, the argument for design, as presented by the natural theologians, is just as good now, if we accept Darwin's theory, as it was before that theory was promulgated; and that the skeptical Juryman, who was about to join the other eleven in an unanimous verdict in favor of design, finds no good excuse for keeping the Court longer waiting.

ART. XXIII-Description of three New Meteoric Irons, from Nel. son County, Ky., Marshall County, Ky., and Madison County, North Carolina; by J. LAWRENCESMITH, M.D., Prof. of Chemistry, University of Louisville, Ky. .

Nelson County, (Ky.) Meteorite.—This came into my possession about two months ago, being obtained from a ploughed field where it may have laid for a considerable length of time, attention was drawn to it by a plough striking it; its metallic character leading the neighboring farmer to believe it to be silver.

It is a flattened mass of tough metal, a little scaly at one corner, being 17 inches long, 15 inches broad, and 7 inches in the o part, shelving off like the back of a turtle, and weighs 161 lbs. -

It is free from any large proportion of thick rust, consequently showing no indications of chlorine. On analysis, the following constituents were found in 100 parts, No. 1 in the table below:

[merged small][ocr errors]

Marshall County, (Ky.) Meteorite.—A piece of this Meteorite was sent to me from Marshall County, in this State. I have not yet seen the entire mass, which is said to weigh 15 lbs., and to be scaly in structure. It has the usual characteristics of meteoric iron, as seen from the analysis, No. 2.

Madison County, (N. C.) Meteorite.—This meteorite was presented to me some time ago by the Hon. T. L. Clingman, of North Carolina. It came from Jewel Hill, Madison County, of that State. There is a great deal of thick rust on the surface, with constant deliquescence from chlorid of iron. Its form and surface indicates that it is entire, its dimensions are 7×6×3 inches, with a number of indentations; its weight is 8 lb. 13 oz. Its composition is given in the analysis, No. 3.

[graphic]

ART. XXIV.-Description of a new Trilobite from the Potsdam Sandstone; by FRANK H. BRADLEY, with a note by E. BILLINGs.

[Read before the Am. Assoc. for the Advancement of Science, at Newport.]

CoNoCEPHALITES MINUTUs, (n. sp.)

Fig. 1. The head magnified. The dotted lines represent the supposed outlines of the parts not preserved.

Fig. 2. The pygidium magnified. Fig. 3. A detached cheek, magnified. Cephalic shield apparently semi-circular, or nearly so; anterior margin as far as preserved with a narrow slightly elevated rim, just within which there is a rather strong groove. Glabella conical, slightly narrowed at the neck segment, three-fourths the whole length of the head, very convex and obtusely carinated along the median line. Neck segment rounded and prominent; neck furrow narrow, but well defined. There are two pairs of deep glabellar furrows which are inclined inwards and backwards at an angle of about 45°; their inner extremities distant from each other rather more than one-third the width of the glabella. The anterior lobe is a little less than one-half the whole length of the glabella, excluding the neck segment; the two posterior pairs are nearly equal to each other. The glabella is distinctly separated from the cheeks by a narrow, deep groove, which extends all round. From the anterior lobe on each side a narrow filiform ridge curves outwards and backwards on the fixed cheek to the edge of the portion preserved. The eyes appear to be situated just where these ridges terminate as represented in figure 1. Judging from the portion of the eye preserved in a detached cheek-plate, its form is semi-annular, and its length at least one-fourth that of the glabella. Its distance must be at least one-half the width of the glabella. Caudal shield nearly as large as the head, its width scarcely equal to half its length ; the lobes nearly equal; the middle lobe very convex with five sharp transverse grooves; the side lobes somewhat flat, and each with five grooves. The largest head discovered is exactly two lines in length. The course of the facial suture has not been ascertained. The surface of the glabella in one of the specimens appears to be smooth, but in none of the others can it be distinguished. AM. JOUR. SCI.--SECOND SERIES, Vol. XXX, No. 89.-SEPT., 1860,

[graphic]
« PreviousContinue »