Also the fruits which fall to the earth and decay; and, in a word, as decay and fungus growth are often associated, so decayed fruit should not be eaten. But it is well-nigh past belief what quaint yet beautiful objects many of these moulds become under the microscope. A mere vegetable stain, which when touched leaves a smut upon the finger, is thus unfolded into a jungle of plants, whose forms are of the most recherché character and wholly defiant of verbal description. In proof, look at the elegant mucedine, or vegetable mould, Dactylium dendroides. Again, examine the pretty hummock named Polyactis fasciculata, from the mould on the outer husk of a horse-chestnut. The quaint Dendryphium fumosum is from a stain of black mould on the angelica; and the grotesquely eccentric Triposporium elegans is from a brand of a velvety black aspect on a barkless spot on an oak. But as these moulds are almost every where, these beautiful forms, which but for the microscope would be invisible and unknown, are beyond number: Let us instance a noble service rendered our common humanity by the microscope. How often, like some spectacular scenes in a drama, do we find in the pages of the OldWorld history passages of deep pathos and fierce passion, and both, alas! occurring as the offspring of religious superstition. So there were miraculous apparitions of blood, one while in rain from the heavens, and again in spots in the dwellings of God and of men. Of course these were portents of DENDRYPHIUM FUMOSUM.-AFTER CORDA. TRIPOSPORIUM ELEGANS.-AFTER CORDA. most dire significance. The recital is too long, for even in Christian chronicles it covers a thousand years. In 1263, shocking to tell, while ministering at the altar of his church at Bolsena, a Bohemian priest was seized with the terrible temptation to doubt the transubstantiation of the wafer which he had just consecrated. Horrified at his own guilt, the celebrant of the mass beheld drops of blood oozing from the sanctified Host. All were awe-stricken at the miracle, and the Church instituted in commemoration the feast of Corpus Christi. Such was the pious legend. In the fourteenth century, when Heinrich von Bulow had destroyed the village and church of Wilnach, as if to show that Heaven was pained at the sacrilege, eight days afterward the Host on the altar was observed to be stained with drops of blood! THE MICROSCOPE. HUMAN BLOOD cells (Live BLOOD).-MAGNIFIED STELLATED BLOOD CELLS (DEAD BLOOD).-MAGNIFIED Palmella cruente. Near the close of that fourteenth century | alga, and bears the name given it by Agardh, Its structure is even simappeared Raphael, a wonderful man, with a genius sublime, with passions groveling, and pler than that of an oidium. The name, withal a religiousness that made him feel though not romantic, is significant. Palmeland pass for devout. In the now celebrated la means a vibration or quivering, and is stanze of Raphael in the Vatican is that here suggestive of that tremulous movement miracle of this painter's genius, "Miracolo of which a great clot of coagulated blood is di Bolsena." Its exhibition at each feast capable. The entire name indicates the sigof Corpus Christi intensified the Church's nificance of "quivering gore." In England conception of the so-called miracle which the popular name of this fungous slime is 66 gory dew." It occurs as shining red films confirmed the faith of the Bohemian priest. Unhappily the bloody portent returned; the or thickish blood-red stains on damp walls, Host was again spotted with gore. The zeal and chiefly on the whitewashed walls of celof the ecclesiastics became insane, for, horri-lars. Being a unicellular plant, when the ble to relate, thirty-eight innocent Jews were burned at the stake. For what? For crucifying the Lord afresh, for torturing the Host until it bled! In 1824 the "blue Moselle" was horrified with a rain of supernatural blood; and again in 1848 this unnatural gore fell from heaven. And now Ehrenberg takes the matter in hand for sober investigation, and the microscope alone is to determine for the This great man dissisuperstitions of men. pated the miracle entirely by exciting wonder in another direction, for he announced that these bloody rain-drops were composed of real living organisms, but so minute was each individual that it would take over forty billions of them to make one cubic inch. cells are mature there is a flowing together into viscous masses, which look and feel unpleasantly like clotted blood. Presenting also this aspect of gore, though not so decidedly, is the Hamatococcus sanguineus of Agardh. Though moist to the touch, this has not the gelatinous character of palmella; hence the bloody illusion is not so vivid. It would be profoundly interesting to follow the work of the microscope in scientific classification. It is beyond all question that the work of the ancient naturalists was trivial in comparison with that of those who are working the field to-day; and in this respect it can not be otherwise than that the lamented Agassiz set too high an estimate on the work of the great Stagyrite. None better than Agassiz knew the value of embryology in the work of the philosophical systematist. But embryology is a science of the present. It was not possible to the ancients. Nor is it possible to-day to the mere zoologist. It needs the microscope in the hands of him who is profound in zoHe ology and an expert in microscopy. Thus the microscope has done away with these grim portents of a thousand years. This red snow and bloody slime have now their distinctive place and names among organic things. They are microscopic vegetables-unicellular plants. In the arctic regions Captain Ross found this encrimsoned snow extending in masses of miles. Among the Japanese the sponge is known brought some home, and the able botanist sea cotton." And until recently this R. Brown pronounced it Algarum genus. It is curious to notice the controversy of so idea of the vegetable nature of the sponge many able botanists, with their diverse judg- was universal. The microscope alone cast ments. But after a while all came back to light into this darkness. The sponge is inthe judgment of Brown; and Agardh, the deed an animal. It is also true that these able German algologist, gave this, the low-sponge animals belong to many genera and liest of the algæ, the name Protococcus ni- species. The work of classification is, howvalis. But about the drops of blood? This also the microscope has determined to be an as 66 ever, so far as the sponges are concerned, one of great difficulty, and without the microscope it is impossible. In general terms, the sponge of the toilet is the skeleton of an | forms, and these forms vary with the speimmense number of sponge animals. This cies, they become of great help in their dehorny skeleton holds the sarcode, or sponge termination. It is noticeable, then, that a flesh. This sarcode surrounds the entire sponge skeleton, when alive, consists of two structure, and, indeed, excepting the open-parts-the one with which we are familiar ings or tubes necessary for inhaling and ex- as the sponge of commerce, and which is of haling, it is also the filling in of the struc- an animal nature, namely, keratose or horn, ture. Now this sarcode is of a consistence and the other the spicules, or filling in of like jelly, and would be diffluent but for the the reticulated horny part; and these spicfact that it con- ules are mineral, either silex or lime. Now tains mixed all the strange exception to all this is with the through it little glass sponges: instance the familiar Japaspiculate parti- nese glass-rope sponge, the hyalonema. Its skeleton is all silex, the long fibres or threads which compose the rope or coil, also the finer structure called the head. The greater part of the head is made of very fine fibres or glass threads, and the filling in is with beautiful spicules of the same material. The whole skeleton, then, is composed of silex. cles of a siliceous Now as showing the authority of the microscope in this connection, we must detail a bit of experience which occurred along with this writing. A scientific friend informed us that he had received direct from have very definite Japan a specimen of hyalonema which was GLASS-ROPE SPONGE (HYALONEMA SIEBOLDI).-ONE-THIRD NATU RAL SIZE SPIOULES OF GLASS SPONGE a unique. We went to see it, and astonishment ensued. It was truly surprisingly fine, and as a specimen, certainly excelled any one that we had ever seen. The head was a deep thin cup, and quite symmetrical, and the whole specimen had a compactness which seemed to say that it had been selected from a thousand. Indeed, it was so fine that we became impressed with the suspicion that it was a fraud; that the head was not that of a hyalonema at all. A small portion of it was subjected to the microscope, which showed up the coarse irregular horny reticulation, such as is not to be found in the glass sponge. As to the spicules, none could be found. It was evident that a piece of the very thin yet large cup-like sponges so common in Japan had been cut out and folded just as the grocer makes a cornucopia. This was put at the top of a real glass rope of hyalonema, and by some cement the whole was so ingeniously secured as to escape observation. We then gave some attention to a true hyalonema. SPICULES OF GLASS SPONGE. prepared for the microscope. Taking a sheet of clean white paper, a hya- | When dry, some glass slips or slides were lonema head was shaken over it. A little dust fell. This was carefully collected and put into a test-tube and boiled in nitric acid. This was intended to destroy every thing except the glass spicules that might be in that intangible dust. A little sedi-sented was a vision of beauty. Forms inment was observable at the bottom of the tube. The acid was carefully removed, and the precious film left on the glass was now washed with scrupulous care. The water was then filtered through bibulous paper. A little stain of dust remained on the paper. numerable appeared as the slide was moved slowly on the stage of the instrument. The variety of these forms was endless, although nearly all could be reduced to a few patterns, of which they were modifications. And every one of these pretty figures was transparent, for they were of natural glass. | has spread, or rather rushed, all over GerMany of them gleamed like pearls. Some many. There is now a sort of neck-andof these forms were so odd, others were so neck race who will make the most slices of exquisite! Crosses were there of indescrib-rocks and minerals. A cutting or rubbing able beauty. Some forms there were that machine and a microscope have become as resembled the knightly lance of the hero of necessary implements as a hammer and a La Mancha. Others were like feathers, and lens. Every month brings to light some some were like churn-dashers. Some sug-new 'mikromineralogische' contribution, ingested snow crystals, and besides their simil- somuch that if the fever lasts we shall ere itude of form, they had the same sparkle too. long be as overweighted with microscopic Many, however, were of forms not easily de-analysis as we used to be with chemical." scribed. As the best that could be done, we But what labor, skill, and patience are have drawn from the microscope some sev-necessary for this sort of work! Take a enty of these hyalonema spicules. There tiny bit of obdurate granite and put it unare two figures among them—the one of a der a microscope, and beyond the enlarging discoidal form, and that one of a truncated of its asperities you see nothing that is reovoid—which, though found among the spic-markable. ules, are plainly shells of some foraminifera which have served as food to the glass sponge. The figures are all greatly enlarged, from 400 to even 1400 diameters, and some even 2000. The petrographer would take it from your hands, and by tedious labor would rub it down until it was as thin as this paper. He would next take this tender, brittle plate, and with manipulations of the utmost delicacy, would polish away every scratch. Now it is transparent, or at least translucent, and under the microscope is revealed a little world of beautiful colors, and a delicate mosaic in structure. But what persevering labor, what matchless skill, and what exhaustive patience are the price of this little object! One of the Spanish adventurers to Mexico in the ancient day on his return home greatly astonished the Castilians by his account of the mineral cutlery of those ancient Mexicans. Their knives were so keen, and they were made so fast-a hundred a minute. There was probably a dash of extravagance here, but only a dash. The material used was a black volcanic glass. It is a hard mineral, at sight much like the material in a black flint-glass bottle. By skillful blows long narrow flakes were struck off from the lump in hand. A single smart blow would strike off one long flake, and each flake was a knife ready for use, and with an edge unexceptionally keen. This substance is known in mineralogy as obsidian. Suppose, now, we look at a bit of this mineral with the eye of an amateur in mineralogy. It is volcanic glass, and it looks just like a piece of black flint-glass. We label it obsidian. To all appearance it is perfectly homogeneous. We put together a number of specimens from different countries, and with the exception of differences of color, we see nothing whatever to distin It would now seem that the microscope is about to "be in league with the stones of the field." At any rate, it is certain that an effort is under way to come at a better understanding in this matter. In fact, for the skilled microscopist a new science has just arisen-that of microscopic petrography. The old method of chemical analysis was thought all-sufficient for the determination of minerals and rocks. All this, so far as it relates to the constructive constituency of rocks, was a species of light which was often little better than darkness. There was a grand advance in that idea which disputed the homogeneity of any rock or crystal, and claimed for every one a specific morphology of its own, if one could but see it; for in this idea of form, where it had been supposed all was formless, might not the genesis of many rocks be explained, and a more rigid classification be achieved? The microscope is now revealing in the rocks a crystallographic idiosyncrasy which is already differentiating the species. We may safely accept this new method as respects the inorganic as of similar worth with embryology in the organic. But we can not resist quoting on this very point some graphic words from Nature: "In the midst of the darkness wherein the poor petrographers ticketed their specimens, carefully arranged their cabinets, and elaborated their dreary treatises, there fell among them (not from heaven, but from the hands of a worthy citi-guish them. Well, is there really any dif zen of Sheffield) a microscope and a few glass slides, with a description of what could be done therewith. Eyes which had seen no light for so long could not at first make any thing of the apparition; but after a few years it began to take shape before them. And now the microscope promises to do as much in comparison for mineralogy and petrography as it has done for the biological sciences. From town to town this new light ference worth talking about? We must put this question to some petrographist. Happily some exquisite engravings on this subject have been just given to the world by H. Rosenbusch, of Germany. Let us now follow him in his labors with his microscope. A bit of obsidian is the subject. At length it is prepared, a thin section or film. It turns out that the seemingly homogeneous mineral is full of queer objects, not unlike |