fibrin. The coagulation of blood is caused by the spontaneous solidification of the fibrin, as a network of filaments, which entangles the blood-globules, and forms a mass called the clot. The albumen remains liquid, and is gradually forced out as the clot contracts. If blood is placed in alcohol, the albumen solidifies in minute granules. The albumen being thirty to forty times as abundant as the fibrin, when both of these constituents are solidified, which takes place when blood or a tissue containing blood is placed in alcohol, the filaments of fibrin cannot be distinguished, as they are concealed by the albuminous granules. The same condition was induced when Mrs. Fero's head was immersed in alcohol. Although the blood had coagulated, the fibres were surrounded by a liquid containing albumen, which soon formed granules, and concealed the fibrin-filaments. Hence it seems unreasonable to believe that Dr. Stevens saw fibrin, as he thought probable. The following question was proposed to the same gentleman (a question which, properly answered, was regarded by the defence as of great importance): "Can you distinguish between a piece of flesh stained only with liquid blood, then soaked in alcohol, and afterwards bruised, and a piece of flesh bruised before death, and then soaked in alcohol?" He replied that he could not distinguish between them.

Dr. Van Derveer found in the specimens examined by him broken ultimate muscular fibres, also some healthy muscular fibres. He likewise stated that he observed fragments of broken blood-globules driven into the ultimate muscular fibres. This statement is of such a character that its mere announcement might be regarded as its sufficient refutation; but, lest injustice be done to the expert who made it, it is proper to submit it to examination. The blood-globules of man have an average diameter of 30th of an inch. They are not solid bodies, but, on the contrary, have a consistency which is very nearly fluid. They are homogeneous, and are not provided with an investing membrane. It is these minute, almost fluid bodies, we are told, which were shattered by blows upon the head, and their fragments-fluid be it remembered forcibly driven into the solid ultimate muscular fibres, the average diameter of which is 4th part of an inch. And this observation, it should be borne in mind, was made not upon fresh blood-globules, but upon the alleged fragments of blood-globules which had been subjected to a five months' immersion in ninety-five per cent. alcohol.

It appears that, after this long immersion of the tissue in alcohol, Dr. Van Derveer swears that he positively identified, as fragments of blood-globules, certain particles which he saw in specimens of the tissue examined under the microscope! Moreover, he swears that he saw these fragments of blood-globules (fragments of fluid bodies) imbedded, like wedges in a log of wood, in the substance of the solid ultimate muscular fibres, where, we are asked to believe, they had been mechanically driven five months before, by the force of blows which were assumed to have been struck upon the head of Mrs. Fero. But, even if we admitted the correctness of the observation, and that blows might produce such effects, of what importance is it in the case, when we are unable to determine whether the condition described was produced before or after death?

Photographs of Nobert's Lines.-Dr. Woodward, of the United States' Army Medical Department, has just presented to the Royal Microscopical Society and to a few private friends, four admirable photographs of the above. The first represents the 1st, 2nd, 3rd, and 4th bands of the 19 band-plate, magnified 1200 diameters by Powell and Lealand's eth immersion. The second represents the 8th, 9th, 10th, and 11th bands of the same plate, magnified 1100 diameters with the same objective. The third displays the 13th, 14th, and 15th bands of the same plate, magnified 1100 diameters with the same objective; and the fourth contains two photos, one a large one representing the 19th band of the 19 plate-band, magnified 1100 with Powell and Lealand's th immersion, and the smaller an enlargement

of part of the other to 2750 diameters.

The Presidentship of the Quekett Club.-It is arranged that Dr. Lionel Beale, F.R.S., is to be the next President of the Quekett Club. It is needless to point out what an excellent selection the club has made, and we have no doubt that it will tend to strengthen that entente cordiale which is now so thoroughly established between the Quekett Club and the Royal Microscopical Society.

Influence of Light on the Cells of Spirogyra.-At the meeting of the Academy of Sciences on the 11th of July, the Montyon prize for Experimental Physiology was awarded to M. Famitzin for his researches, which have determined the precise action of light on the increase of the cells of Spirogyra, and on the development of the green

matter.

Möller's Test-slide and the Navicula Lyra Photographed.-As illustrative of photo-micrography with the oxy-calcium light, a subject reported on by Col. Woodward, of the U. S. army, in our present number, the author has sent to the Editor and to the Royal Microscopical Society exquisite photographs of the above. The representation of Navicula is about 4 inches long, and is wonderfully well defined. That of Möller's curious collection of Diatomacea is not so good, owing to some of the specimens appearing simply as black disks. The Navicula is magnified 1000 diameters with Powell and Lealand's th immersion; the test-slide is magnified 35 diameters, with one of Wales' 1-inch object-glasses.

French Prizes for Microscopical Researches.-At the meeting of the French Academy of Sciences on July 11th, the Desmazières prize was equally divided between MM. Hoffman and Rabenhörst; the first, author of a memoir on Bacteria, and the second for his work 'Flora Europæa Algarum aquæ dulcis et Submarinæ.' At the same time "honourable mention was accorded to M. Edouard Strasburger for two memoirs " On the Sexual Organs and the Fecundation of Ferns."

وو

Blankley's Universal Revolving Stage. We give an illustration of Blankley's Universal Revolving Stage, a description of which was read before the Royal Microscopical Society, and appeared in this Journal,* so that it is only necessary to give an explanation of it here. * Vol. iii., p. 209.

Fig. 1 shows the stage itself with a live box (which can be used with the spot lens) placed in the centre; and by rotating the milled disk shown at the edge, the object can be viewed at every angle of

light. Fig. 2 is the mounted object-holder for transparent or opaque

slides, and fits into Fig. 1.

object that may be wished to

Fig. 3 is a cork disk for pinning on any be seen in various positions.

CORRESPONDENCE.

THE DEFINITION OF NOBERT'S LINES.

To the Editor of the Monthly Microscopical Journal.'

WASHINGTON, D.C., June 18, 1870. DEAR SIR,-The May number of the Journal contains on page 257 et seq. a letter from Mr. Charles Stodder, of Boston, in which that gentleman reasserts the claim made in his paper published in the 'American Naturalist' of April, 1868, that he and Mr. Greenleaf had resolved the 19th band of the Nobert's plate with an immersion 1th, made by Mr. Tolles, of the Boston Optical Works, and alludes to me in a manner which seems to require some reply. His letter is followed, in the same number, by one from Mr. R. C. Greenleaf, in which that gentleman states his agreement with Mr. Stodder's opinions, and talks about "the honor of our American instruments."

Mr. Stodder writes with a warmth which will be best understood when it is known that he is the treasurer and agent of the Boston Optical Works, the establishment at which Mr. Tolles produces his really very excellent lenses, and that he has for some time claimed

that Mr. Tolles produces the very best lenses in the world. I am not willing to yield to either of these gentlemen in the disinterestedness of my desire for the success of American opticians, but am of the opinion that our progress will be hindered rather than helped if we shut our eyes to the few cases in which English or other manufacturers excel ours. In fact, where this is the case a recognition of the reality appears to me necessary to our progress.

Mr. Stodder's complaint that his paper in the 'American Naturalist' has been ignored, certainly cannot apply to me. In my first essay on the Nobert's plate,* I quoted from it, and gave the reasons why I thought Messrs. Stodder and Greenleaf had been misled by spurious lines. At that time I had not been able to resolve any band beyond the 15th, and I did not succeed with the 19th until I obtained the immersionth of Powell and Lealand in the spring of 1869. So that if Messrs. Stodder and Greenleaf's original claims were really well founded, they certainly ante-dated mine. Nevertheless, I still think they were at that time mistaken, and do not now believe that the th, with which they at present claim to have resolved the lines, has really succeeded in doing so. I will endeavour to state very briefly my reasons for this opinion.

In my judgment it cannot be said that one of the bands of the Nobert's plate is resolved unless the lines are shown in such a manner that they can be correctly counted from one edge of the band to the other. Objectives of inadequate defining power can easily be made to show lines in the higher bands which would deceive even an experienced eye, and the lower the power the more readily the observer will be misled; but if such spurious lines are counted, they will be found too few in number, and their nature is thus shown. Now, not only did Mr. Stodder in his original paper admit that he had not counted the lines, but he fell into a grave error on the subject of counting fine lines, which he expressed in the following words :-" In counting lines of such exquisite fineness either the micrometer or the stage must be moved, and it is next to impossible to construct apparatus that can be moved at once the 1000ooth part of an inch and no more.' In consequence of this error, Mr. Stodder had omitted the only reliable mode of demonstrating that he had not been misled. My paper led to some correspondence between him and myself, in the course of which I endeavoured to borrow the lens in question for the purpose of testing it. I then learned that it had been unfortunately broken. Other ths and ths, made by Mr. Tolles, which from time to time I had an opportunity of testing, did not in my opinion justify the claims made. In the latter part of May, 1869, I received for inspection the so-called th, with which Mr. Stodder now claims that he has resolved the 19th band. I was, however, unable to push it beyond the 16th. Mr. Stodder had requested me to send it, in case I did not succeed with it, to Mr. W. S. Sullivant, of Columbus, Ohio, a gentleman whose reputation for skill as a microscopical manipulator stands deservedly high in this country. Mr. Sullivant wrote me, July 11, 1869 :— "The Tolles' immersionth I returned to Mr. Stodder, who wrote me about

* 'Quarterly Journal of Microscopical Science' for October, 1868, p. 225.

it. Tolles marked the grade of that objective too high. It is hardly anth English standard. You put it up to high-water mark in making it resolve the 16th band. I was satisfied in getting it well through the 15th, and took the 16th partly on trust." Nevertheless, after this lens got back to Mr. Stodder, lines were shown with it which it seems a number of my friends in Boston believe were the real ones, though none of them appear to have made a count, which, after all, is the decisive test. I still believe that my friends were deceived by spurious lines, and have greatly regretted that I could not drop in on them, and look over the shoulder of Mr. Tolles (who is regarded not only as the champion maker of objectives, but as the very best manipulator of his own lenses) to see what it was he really saw. Fortunately this has recently been done by a disinterested witness. In Max Schultze's Archiv für Mikroskopische Anatomie' (Band VI., S. 205) there has just been published an interesting article by Dr. H. Hagen, "Ueber die Mikroskope Hordamerikas." Dr. Hagen is a German gentleman who has recently settled at Cambridge, and who has been appointed a professor in Harvard College. Since he wrote the paper above quoted, he has paid a visit to the Army Medical Museum, and I have had a long conversation with him about it. I found him well instructed in microscopical matters, and must regard him as a competent witness. He relates on page 216 how Mr. Tolles himself undertook to show him the 19th band with an immersionth, which I understand from him to be the very one in question. He showed him lines indeed, but he was unable to count more than forty of them. Mr. Tolles himself counted between forty and fifty. These counts show that the lines in question were spurious. Dr. Hagen concludes, as the result of his examination of the lenses of Tolles, that in a general way they are quite as good as lenses of the same power by the best European makers, but that they cannot be said to excel all others, since as yet none of them have resolved the last four bands of the Nobert's plate, as theth immersion of Powell and Lealand has done.* He naïvely relates that his unwillingness to admit more was not favourably received by the Boston microscopists. "Ich kann nicht unterlassen zuzufügen, dass schon mein Versuch, ein Urtheil über die hiesigen Instrumente zu fällen und europäische denselben gleich hoch zu stellen, einen Sturm der Indignation unter den hiesigen Mikroskopikern hervorgerufen hat. Ihre Indignation wird mehr erklarlich, wenn man weiss, dass sie fast sammtlich der Boston optical Association angehören, die bis jetzt ohne Zinsen arbeitet.†

After this testimony of Dr. Hagen I must be pardoned if I continue my disbelief until some evidence more positive than mere opinion is offered.

6

As to whether I saw the true lines with the th of Powell and Lealand, I may simply remark that I supported my statement by a count of the lines as well as by the photographs made by Dr. Curtis. I thought, and still think, that Dr. Curtis's photographs were conclusive evidence that I had seen the true lines, although the spurious lines shown on the edges of the band prevented them from serving for † Page 208.

*See page 217 of his paper.