64 LIST OF PATENTS FOR NEW INVENTIONS, Which have passed the Great Seal since November 26, 1829. To Francis Westby, of Leicester, in the county of Leicester, cutler; for certain improved apparatus, to be used for the purpose of whetting or sharpening the edges of the blades of razors, penknives, or other cutting instruments. Dated November, 26, 1829. -To be specified in two months. To John Marshall, of Southampton-street, Strand, in the county. of Middlesex, tea dealer; for a method of preparing or making an extract from cocoa, which he denominates Marshall's extract of cocoa. Dated December 10, 1829.-In two months. To Benjamin Goulson, of Pendleton, near Manchester, in the county of Lancaster, surgeon; for certain improvements in the manufacturing of farina and sugar, from vegetable productions. Dated December 14, 1829.-In six months. To Charles Derosne, of Leicester-square, in the county of Middlesex, gentleman; who in conscquence of a communication made to him by a certain foreigner residing abroad, and inventions by himself, is in possession of an invention, for certain improvements in extracting sugar or syrups from cane juice, and other substances containing sugar, and in refining sugar and syrups. Dated December 14, 1829.-In two months. GILL'S TECHNOLOGICAL & MICROSCOPIC REPOSITORY. XIII. Additional Particulars on viewing the Circulation of the Sap in the Chara Translucens. By THOMAS CARPENTER, Esq. With Remarks. By the EDITOR. DEAR SIR, WITH FIGURES. London, January 1, 1830. I WAS so highly gratified with seeing the circulation of the sap in the stem of the chara translucens, under your excellent Varley's single microscope, last evening, that I was induced, this morning, to try what effect I could produce with the small portion of the plant you gave me, under my compound microscope. Having cut off one of the joints, which was the farthest from the root, I scraped off the green bark very carefully, until I had rendered it transparent. I then placed it within some water in a watch glass; in this state, I had the pleasure of seeing the circulation in a very distinct manner (but not equal to the view under your Varley's microscope), the globules proceeding down one side of the stem, and going up on the other side, resembling very much in appearance the slow circulation of the blood, which we have frequently seen in some of the smaller aquatic insects. Your microscopic readers will now have an opportunity of witnessing this very interesting fact, as almost any well constructed compound microscope will produce the effect. VÒL. VI. F I imagine that if the other species of chara, as well as numerous other aquatic plants, were to be treated in the manner in which I have prepared the chara translucens, that the circulation of their sap might also be seen in several of them. When you are viewing this plant again, I would recommend you also to examine the various animalculi which attach themselves to it. I observed several which were quite new to me, and some of which were of most singular forms. One, in particular, attracted my notice; it was an elegant lively little creature, furnished with a membrane, which it occasionally threw up, after the manner of the nautilus, and which seemed to assist it in its motions in the fluid; and when in that state, it very much resembled that marine animal in miniature; should you observe it, perhaps you will favour your readers with a figure of it. I remain, dear sir, Your obliged friend, To T. GILL, Esq. THOMAS CARPENTER. Remarks. By the EDITOR. It is very true, that, knowing the circulation of the sap to exist in the chara translucens, it may be traced under the compound microscope, as the Editor has done in one made by the late celebrated George Adams, in his possession; but he certainly would never have been enabled to have discovered it by that instrument. Since his communication in last month's number, the Editor has found that the two portions of the chara which he had separated from the plant, and prepared for viewing by the microscope in the manner there described, retained their power of circulating the sap for at least fourteen days after such separation. This is indeed a most surprising fact, and what could not have been expected, as the plant itself had then been gathered at least six weeks; and, indeed, the remainder of it has now lost its power of circulation from decomposition. Mr. Gray informs the Edi-. tor, that the plant is yet to be found, it growing in spring water, three feet in depth, and below the reach of frosts. It is, however, a valuable discovery, that the prepared parts of it, when kept under water, will retain their circulating power so long. The two portions thus separated, are each not more than three quarters of an inch in length, and about the tenth part of an inch only in thickness. In plate II. fig. 1 represents one of these portions, as being surrounded with a little water, when placed upon a slip of glass, and ready for examination under the microscope. fig. 2 is a magnified view of part of the exterior of it, which is irregularly granulated. And fig. 3 represents the interior of the sapvessels, as they appear when the sap is seen flowing through them, by altering the focus a little, when the outer granulations disappear, and the inner parts of the vessels appear to be finely ribbed and granulated. It may be remarked, that the Editor divided the last specimen of the chara which Mr. Gray furnished him with, into two portions, one of which he placed in a Wedgewood's mortar, and only just covered it with water; and the other in a tall glass jar, four inches deep in water. The first continued alive; but the other soon became black, and was quickly decomposed. XIV. On the Microscope. By THOMAS CARPENTER, Esq. With Remarks and Additions. By the EDITOR. DEAR SIR, WITH FIGURES. (Continued from page 8.) London, January 10, 1830. ACCORDING to the promise I made in my last letter, I now send a variety of objects for your microscope, which I trust, on examination, you will find interesting. I have before observed, that the farina of various plants affords abundant employment for the microscope; the whole of those I now send may be viewed either as transparent or opaque objects; the latter method, however, I prefer, under high magnifying powers, inasmuch as the fine colours are preserved, as well as the shape and characters in each species. Mr. Needham has pointed out a very interesting method of viewing the expansion and bursting of the various globules of farina, by placing a few of them within a drop of water, on the stage of the microscope; and when at its proper focus, by attentively observing, they will be seen to burst, and discharge an apparently dark fluid, but which is in fact composed of numerous minute globules, that tend to the fertilization of the seed contained within the plant. For much interesting information on the farina, I beg to refer you to Stillingfleet's preface, page xxx., and also to page 58; also to Derham's "Physico Theology," vol. II. page 383; and for the experiments made by Needham, see his work on the subject, page 60. Among the various kinds of farina I have sent, you will find some from the sunflower, the hollyoak, the marvel of Peru, the blue bell, garden flag, strawberry, orange flower, arbutus, moth flower, garden mallow, convolvulus, palm tree, tulip, Canterbury bell, tyger lilly, white lilly, Guernsey lilly, salvia coccinia, scarlet fuschia, major convolvulus, and larkspur. These are all placed between slips of glass, and among them will be found some which I have tried Mr. Needham's experiments upon, and succeeded in producing the effects above described, which you will perceive are still very visible, on your examining the same under your microscope. With these you will also receive three cast skins from spiders, on which you will observe curious hairs, some of them of a herring-bone shape; other hairs branching out from them. A few fine scales, taken from the head of a lepisma, are also in the sliders containing the cast skins of the spiders. I likewise send you some hairs, placed be |