ducts and the deep-seated lymphatics of the liver. Both Kiernan and Mascagni noticed that injections thrown into the ducts returned by the absorbents, and the former observer stated that bile is frequently propelled into the absorbents on injecting the duct; and it is known that in some diseases of the liver the hepatic lymphatics are found to be distended with bile.

Sponges or Worms.-In a paper read before the Montreal Natural History Society, on the 29th of November, "On the Genus Scolithus and some Allied Fossils." Mr. Billings attempted to prove that the well-known fossil Histioderma Hibernicum from Bray in Wicklow are really not the casts of an annelid, but are, as their structure seemed to show, veritable sponges.

A Microscope and Camera combined.-Those who care for the multum-in-parvo class of apparatus will do well to read the description (British Journal of Photography,' January) of a new instrument invented by MM. Borie and de Tournemine, and exhibited at a meeting of the French Photographic Society. The description of the instrument is too long for our pages. But we may state that, according to the inventor, the apparatus may be used as the following separate instruments :-A solar microscope, a photographic solar microscope, a compound microscope, a photographic apparatus, an enlarging apparatus for negatives, a terrestrial telescope, a telescopic photographic apparatus, an enlarging apparatus direct upon paper, and a photographic ophthalmoscope.

NOTES AND MEMORANDA.

Soirée of the Old Change Microscopical Society.-We learn from the secretary, Mr. S. Helm, that the fourth annual soirée of this Society will take place at the City Terminus Hotel, on the 14th inst. Gentlemen desirous of exhibiting objects at the soirée should communicate with the secretary without delay.

Microscopy in Dublin.-The following quotation from "The Medical Press Circular' of the 19th of January, needs no comment from us; its force will be fully apparent to our readers :-" Dr. John Barker read an interesting paper On Microscopic Illumination' at a meeting of the Royal Irish Academy on the 10th inst. Dr. Barker truly describes the present defective manner of viewing microscopic objects, by saying that ordinarily on looking into a microscope we feel disposed to shrink from the sudden glare of light which strikes on the eye from the field of vision, which is flooded with intense light; the pupil contracts, and at first we see nothing at all; presently a something semi-transparent is rendered visible by the relative opacity and transparency of its parts, and by the shadows they cast on the

Microscopica

retina and on other portions of the object. Now, all these effects will not show us its true structure, but will rather contribute to a false impression of what is under examination. From such considerations as these, Dr. Barker concludes that axial illumination, in which a large portion of the central rays of light are stopped off, is the only one which ought to be admitted in microscopic research- -a conclusion already arrived at by most of our best microscopists; but all have hitherto experienced a great difficulty in obtaining sufficient light, and of economizing the oblique rays (those most valuable), which are generally reflected to a large extent, and even dispersed at the under surface of the slide on which the object is placed. To obviate these difficulties, Dr. Barker makes use of the immersion plan, by placing between the slide and illuminator a film of water or oil; this gets rid of all, or almost all, the defects of former modes of illumination. This film acts as a medium, permitting rays of light, without sensible deviation or dispersion, to reach the object, and also allows all stage movements to be freely used. The light obtained in the manner indicated is almost purely achromatic, and is sufficiently oblique to give a black-ground illumination with an eighth of an inch object-glass (immersion), and will show clearly the dotted structure of the lines on the Pleurosigma formosum with a quarter-inch object-glass, and with a two-thirds used binocularly the surface and interior of certain classes of objects are shown in a manner hitherto not seen. Dr. Barker's first experiments were with a flat-topped paraboloid, and, after the meeting of the Academy broke up, the members had an opportunity of viewing with it a specimen of the Conocholus volvox (a truly beautiful object)."

The Quekett Club's Journal.-We are informed that the committee of the Quekett Club have re-considered their recent determination. It is now proposed to issue the 'Journal' of the club as heretofore.

Dr. Woodward's Paper.-The figure omitted in the publication of this paper will be supplied, printed on a separate "slip," in our next. Readers will then have an opportunity of inserting it in the proper place in their volumes.

CORRESPONDENCE.

NOBERT'S TEST-LINES.

To the Editor of the Monthly Microscopical Journal.

148, CHEAPSIDE, E.C., January 12, 1870. SIR,-In p. 283 of the Journal for November last, the reporter of the discussion on Dr. Woodward's paper appears to have quite misunderstood my remarks. I did not say that Messrs. Powell and Lealand had "ruled a test-object with 100 lines in Too," which is a mistake. I expressed a doubt whether the lines on Nobert's testplate could be clearly defined beyond the 16th group. I added that with Powell and Lealand's new method of oblique illumination the lines on the Amphipleura pellucida and acus could be clearly shown with their immersion 1th, th, and th, which also give a beautiful definition of the Podura scales. Mr. Lealand has succeeded in counting the Amphipleura lines, and finds them 100 in Tooth of an inch.

COLLINS' DISSECTING MICROSCOPE.

ELLIS G. LOBB.

To the Editor of the Monthly Microscopical Journal.

January 13, 1870. DEAR SIR,-In reply to the letter of Dr. Swintard, of the New York College of Veterinary Surgeons, I should be glad to explain that if I adopted any plan (invention I did not presume to call it) of Dr. Busteed's it was quite unknown to me; but there is one part of my arrangement that I find much appreciated, and is, I think, novel.

If the engraving is examined it will be seen that the arm is in two portions; the lower half with the objectives is fixed, and the upper half carrying the body turns upon a centre, so that it can be instantly converted from a single microscope to a compound, or vice versâ. It is also fitted with my new double nose-piece, so that the changes of power can be most easily and quickly effected.

Before Dr. Swintard's letter appeared, I was engaged in carrying out a suggestion of Mr. Westell's; this is now nearly completed, and will greatly add to its value as a dissecting microscope, and at the same time remove it from any apparent similarity to that made by Mr. Grunow.

I am, sir, your obedient servant,
CHAS. COLLINS.

PROCEEDINGS OF SOCIETIES.*

ROYAL MICROSCOPICAL SOCIETY.

KING'S COLLEGE, January 12, 1870.

The Rev. J. B. Reade, M.A., F.R.S., President, in the chair. The minutes of the previous meeting were read and confirmed. A list of donations to the Society was read, and a vote of thanks given to the respective donors.

Mr. Slack announced that Messrs. Gould and Porter had sent for exhibition a specimen of their small cheap education microscope; and that the Rev. T. H. Browne, of High Wycombe, had presented to the Society a box containing one dozen slides of carefully prepared sec

tions of bone.

A vote of thanks was passed to Mr. Browne.

Mr. Slack also said he had been requested to state that at the next meeting of the Society (which would be the annual meeting) a proposition would be brought forward to discontinue the practice of providing refreshments after the ordinary meetings, as it was found that less than half the Fellows who attended availed themselves of the provision made, and that in lieu thereof a friendly conversazione should be held. By this means a saving of some 167. to 201. per annum would be effected, which might be advantageously appropriated to the purchase of books and apparatus. The Council had no wish to influence the decision of the Fellows, but thought it worthy of their consideration.

The President proposed that M. Mouchet, of Rochefort-sur-Mer, should be elected an Honorary Fellow of the Society. M. Mouchet was an ardent microscopist, and would feel much pleasure in being more intimately connected with the Society. He had obtained some distinction for inventions in relation to microscopical apparatus, for one of which (a method of cutting wood for microscopic examination) he had received from the French emperor at the late Exhibition a gold medal of honour. He had also devised a finder of more extended application than Maltwood's, for not only could the objects be found, but also accurately measured. The President then read a short communication from M. Mouchet referring to his machine for cutting thin sections of wood.

The ballot was then ordered to be taken for the election of M. Mouchet.

Mr. J. Beck was happy to add his testimony to M. Mouchet's character as a diligent student of microscopy, and very cordially supported the proposition of the President.

The list of Fellows who would be proposed as officers of the Society at the annual meeting in February was then read.

*Secretaries of Societies will greatly oblige us by writing their reports legibly -especially by printing the technical terms thus: Hydra-and by "underlining" words, such as specific names, which must be printed in italics. They will thus ensure accuracy and enhance the value of their proceedings.-ED. M. M. J.

Journal,

It was proposed and seconded, and unanimously agreed to, that Messrs. Suffolk and Bocket be requested to act as auditors for the year.

The President then requested Mr. J. Browning, F.R.A.S., to read his paper "On a Method of Measuring the Position of Absorption Bands with a Micro-spectroscope."

Mr. Ingpen inquired whether Mr. Browning did not think that two lines crossing at an acute angle, as in his (Mr. Browning's) star-spectroscope, would be preferable to a single vertical line; as he thought the position of a band or line in the spectrum could be more accurately measured if caused to bisect an angle than if covered by a bright line.

Mr. Browning thanked Mr. Ingpen for his suggestion, and he thought much advantage would arise from its adoption.

Mr. Brooke said it appeared to him that Mr. Browning's invention was a very valuable one, as it rendered micrometric measurement very simple. The use of a micrometer with a bright image instead of a dark image would be very advantageous; for whereas on a slightly illuminated field the dark image is invisible, by substituting the bright line for the dark line every purpose is answered.

Dr. Lawson said he felt much indebted to Mr. Browning for his invention. He had worked for some time past with the interference scale of Mr. Sorby, but had met with the difficulties which Mr. Browning had enumerated, but he had always been unable to calculate easily the number of the bands lying between the 1st and 12th. The invention just described would make such an operation easy for the future.

The President, in presenting the thanks of the meeting to Mr. Browning, said that the improvements made by him in the construction of the micro-spectroscope were felt by all to be very valuable. It appeared as if the wonders capable of being revealed by this instrument were only beginning to dawn upon those who used it.

Mr. Hogg then gave a brief account of Mr. Alfred Sanders' paper "On an Undescribed Stage of Development of Tetrarhyncus corollatus." The thanks of the meeting were then given to Mr. Sanders.

The President called upon Mr. W. S. Kent to read his paper "On the Calcareous Spicula of the Gorgonacea."

Mr. Stewart inquired of Mr. Kent whether he had come to any conclusion as to the mode of the formation of the spicules he had described. There were instances of agreement in form, but of difference in construction; as in those cases where there was an intermixture of horny and calcareous matter. His own opinion was that this compound structure was due to the molecular coalescence of carbonate of lime deposited in the colloid matter of the animal, thereby modifying the physical forces always operating in the animal.

Mr. Kent replied that he had not paid sufficient attention to this part of the subject to be able to arrive at any conclusion thereon.

Mr. Stewart again inquired how Mr. Kent accounted for the fact that in the flask-shaped spicules the bases projected towards the outside, and the neck was directed towards the axis of the gorgonia? It