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INSTRUMENT FOR ILLUMINATING THE EYE.
294 means for detecting the presence of bluod in almost unappreciable quantities. The prepresent ; e lce of poisonous metals, again, such as arsenic, antimony, mercury, copper, lead, &c., can readily be demonstrated by The practical applicameans of their respective spectra. tion of the spectroscope in clinical medicine is still, however, extremely limited. Nor can much advance be expected in this direction till clinical observers are made familiar with the practical working of the instrument. Dr. MacMunn’s work appears to us admirably suited for this purpose. It is simple in style, lucid in exposition, and modest in tone. The first two chapters are devoted to a consideration of the various kinds of spectra, with a description of instruments and methods for using them. Chapter 3 deals with the application of the study of bright line spectra to medicine, particularly drawing attention to the late Dr. Bence Jones’s researches in determining the time that salts take to reach various tissues and organs. Chapters 4, 5, and 6 treat of the absorption spectra of blood, and give easy methods of preparing most of the important spectra which have been hitherto described. Speaking of a simple process, by which the important spectra of hsematin and cruentin can be procured, Dr. MacMunn states, that it was not till after he had studied Dr. Thudichum’s method that he was able to procure the various decomposition products of haemoglobin by simple and rapid means. Dr. MacMunn thinks that this gentleman’s method ought to be more generally known, and takes this opportunity of observing, " that he has not been sufficiently thanked by the members of his own profession for the great and valuable additions to our knowledge of pbysiologicalandpathological chemistry which he has made." Aswe have lately been inconflict withDr. Thudichum with respect to another matter, we have pleasure in giving prominence to this just tribute with regard to the value of his scientific researches. Chapter 7 gives an account of the absorption spectra of bile, urine, &e. Reference is made to the pathological importance of Jaff6’s isolation of the pigment, which gives an absorption band at F, for this pigment appears to be identical with the uro-bilin, which Dr. MacMunn has found in every specimen of healthy human urine. With regard to urine, there is only one pigment which gives a well-marked absorption band, and this is the pigment just named (uro-bilin). Dr. MacMunn remarks that this is the pigment which ought to have the greatest attention paid it by clinical observers, for, although constantly present in healthy human urine, it is sometimes absent in disease, though in what diseases it is absent he is at present unable to say. Another bile pigment, according to the author, besides uro-bilin, which does not, however, give the characteristic colouration with Gmelin’s test, occasionally appears in certain morbid conditions of the urine. It was found to occur in the following specimens of urine :1. Taken from cases of rheumatic fever. 2. Pregnancy (sixth month). 3. Thoracic aneurism accompanied with albuminuria. 4. Cirrhosis of the liver. 5. Cancer of the pylorus. As a second absorption band has never been obtained in some hundreds of specimens of urine from patients suffering from trifling ailments, Dr. MacMunn infers that it only appears in those cases where there is undoubted disease of a severe character.
only
reliable
when
,
____________
OUR LIBRARY TABLE.
1’epoot by Dr. Milne Robertson upon Certain Peculiar Habits and Customs of the Aborigines of TYestern Australia. By Dr. A. MILNE RoBERTSON, Surgeon, Convict Establishment, Western Australia.-This brief report has been prepared " for the information of gentlemen of the medical and other scientific professions,and to accompany the collection of weapons, implements, &c. sent to the exhibition at Sydney, N.S.W., 1879. It relates to the practice of cir-
cumcision at the age of puberty, and also to slitting the at puberty, among certain families of the aborigines of Western Australia. The two practices are not found to exist together in the same group of families, and the families slitting the urethra differ as to the extent to which the slit is carried. Dr. Robertson’s account is full of interest to the anthropologi,,,t. A Brie A ccount of the .N ativcs of lf7estei,)t A llstralia, their Character, Manners, and Customs. Prepared under instructions from H.E. Major-Genaral Sir N. H. GEORGE ORD, K.C.M.G., C.B., Governor jf the Colony.-An ex. cellent summary account, written to illustrate the collection of weapons, implements, &c. sent to the exhibition at Sydney, New South Wales. A Systematic Course of Practical Qualitative Analysis. By THOS. ELTOFT, P.C.S., P.I.C. London: Simpkin, Marshall, and Co. 1879.-We fail to perceive any real ad. vantage possessed by this little book beyond that of being printed in strong clear type. There are already too many small text-books of the kind.
urethra, also
INSTRUMENT FOR ILLUMINATING THE EYE. To the Editor
of
THE LANCET.
SIR,-A difficulty ophthalmic surgery is met the made by by Mr. James E. Adams in his resuggestion common
in
marks on " an instrument for illuminating and magnifying the anterior parts of the eyeball." A small black foreign body on the cornea near its centre, especially if the iris is dark-coloured, is absolutely invisible to the naked eye, even in a good light; but with the aid of a convex lens and focal illumination, by means of a second lens, is easily discovered. When discovered, however, its removal is extremely difficult without skilled assistance. Mr. Adams’s instrument overcomes this difficulty, though I venture to think that the use of a pair of spectacles (with biconvex glasses of, say, teninch focal length) worn by the surgeon is a simpler and better way of obtaining the magnified image, and obviates certain disadvantages attending Mr. Adams’s method. The lens fixed to the patient’s head must have a more or less limited range of motion, whereas the observer, with a pair of spectacles on his nose, can alter the line of observation to any required angle. The fixed lens, too, may puzzle the observer by the reflected image of the surrounding objects if not set carefully, and this is not the case with the use of the spectacles. If therefore Mr. Adams’s apparatus is employed, I would suggest that the lens for magnifying the image should be dispensed with altogether, and the spectacles be used by the operator. The focal illumination may also be dispensed with in good daylight, and even in the absence of daylight the benzine lamp supplied by Messrs. Krohne and Sesemann answers every purpose in the majority of cases. There will, however, still be exceptional occasions in which Mr. Adams’s instrument, with the modifications of form that I suggest, would be a valuable addition to our resources. The use of spectacles is not necessary for myopic surgeons, but for the emmetropic, hypermetropic, or presbyopic will be found of great value, and, when once tried, will not be easily laid aside for the merely fanciful objection that their use is, perhaps, regarded by the patient as a confession of inefficiency. The successful issue of an operation will easily reconcile the patient to any such imaginary defect in the operator. Even focal illumination and a magnified image sometimes fail to give the information required in the search for a foreign body. The illumination of the pupil by the ophthalmoscope is then the most efficient method; and when the two methods are resorted to any doubts as to the depth of the foreign body, as to its having penetrated deeply into the cornea, as to its having passed into the anterior chamber, and whether it has penetrated or wounded the lens, will be much more satisfactorily solved than if one method only has been resorted to. The same reasoning will apply to traumatic lesions, or the result of disease in the same regions without the presence of a foreign body. I am, Sir, yours, &c., W. SPENCER WATSON, F.R.C.S. Feb. 6th, 1880.
only
reliable
when
,
____________
OUR LIBRARY TABLE.
1’epoot by Dr. Milne Robertson upon Certain Peculiar Habits and Customs of the Aborigines of TYestern Australia. By Dr. A. MILNE RoBERTSON, Surgeon, Convict Establishment, Western Australia.-This brief report has been prepared " for the information of gentlemen of the medical and other scientific professions,and to accompany the collection of weapons, implements, &c. sent to the exhibition at Sydney, N.S.W., 1879. It relates to the practice of cir-
cumcision at the age of puberty, and also to slitting the at puberty, among certain families of the aborigines of Western Australia. The two practices are not found to exist together in the same group of families, and the families slitting the urethra differ as to the extent to which the slit is carried. Dr. Robertson’s account is full of interest to the anthropologi,,,t. A Brie A ccount of the .N ativcs of lf7estei,)t A llstralia, their Character, Manners, and Customs. Prepared under instructions from H.E. Major-Genaral Sir N. H. GEORGE ORD, K.C.M.G., C.B., Governor jf the Colony.-An ex. cellent summary account, written to illustrate the collection of weapons, implements, &c. sent to the exhibition at Sydney, New South Wales. A Systematic Course of Practical Qualitative Analysis. By THOS. ELTOFT, P.C.S., P.I.C. London: Simpkin, Marshall, and Co. 1879.-We fail to perceive any real ad. vantage possessed by this little book beyond that of being printed in strong clear type. There are already too many small text-books of the kind.
urethra, also
INSTRUMENT FOR ILLUMINATING THE EYE. To the Editor
of
THE LANCET.
SIR,-A difficulty ophthalmic surgery is met the made by by Mr. James E. Adams in his resuggestion common
in
marks on " an instrument for illuminating and magnifying the anterior parts of the eyeball." A small black foreign body on the cornea near its centre, especially if the iris is dark-coloured, is absolutely invisible to the naked eye, even in a good light; but with the aid of a convex lens and focal illumination, by means of a second lens, is easily discovered. When discovered, however, its removal is extremely difficult without skilled assistance. Mr. Adams’s instrument overcomes this difficulty, though I venture to think that the use of a pair of spectacles (with biconvex glasses of, say, teninch focal length) worn by the surgeon is a simpler and better way of obtaining the magnified image, and obviates certain disadvantages attending Mr. Adams’s method. The lens fixed to the patient’s head must have a more or less limited range of motion, whereas the observer, with a pair of spectacles on his nose, can alter the line of observation to any required angle. The fixed lens, too, may puzzle the observer by the reflected image of the surrounding objects if not set carefully, and this is not the case with the use of the spectacles. If therefore Mr. Adams’s apparatus is employed, I would suggest that the lens for magnifying the image should be dispensed with altogether, and the spectacles be used by the operator. The focal illumination may also be dispensed with in good daylight, and even in the absence of daylight the benzine lamp supplied by Messrs. Krohne and Sesemann answers every purpose in the majority of cases. There will, however, still be exceptional occasions in which Mr. Adams’s instrument, with the modifications of form that I suggest, would be a valuable addition to our resources. The use of spectacles is not necessary for myopic surgeons, but for the emmetropic, hypermetropic, or presbyopic will be found of great value, and, when once tried, will not be easily laid aside for the merely fanciful objection that their use is, perhaps, regarded by the patient as a confession of inefficiency. The successful issue of an operation will easily reconcile the patient to any such imaginary defect in the operator. Even focal illumination and a magnified image sometimes fail to give the information required in the search for a foreign body. The illumination of the pupil by the ophthalmoscope is then the most efficient method; and when the two methods are resorted to any doubts as to the depth of the foreign body, as to its having penetrated deeply into the cornea, as to its having passed into the anterior chamber, and whether it has penetrated or wounded the lens, will be much more satisfactorily solved than if one method only has been resorted to. The same reasoning will apply to traumatic lesions, or the result of disease in the same regions without the presence of a foreign body. I am, Sir, yours, &c., W. SPENCER WATSON, F.R.C.S. Feb. 6th, 1880.