REMARKS ON THE CIRCULATING SYSTEM.

794

ECONOMIC FORMULA FOR HYDRIO- perfectly pure, which, in commerce, I believ to be seldom the case. I therefore choose t DATE OF POTASH. get my solution prepared as above, of a amber colour, showing the iodine to b To the Editor of THE LANCET. slightly in excess, and I afterwards ad SIR:—As the hydriodate of potassa is a few drops of the liq. potassae, until tb

remedy in very general use, the fol. lowing formula, by which it may be obtained extemporaneously, and at one-half of the price of the crystals, I have tested by some years experience; It has also the additional advantage of the prescriber knowing exactly what he is administering, as the crystallised hydriodate, in consequence of its high price, is very frequently adulterated. Rub together as much iodine and potassa

now a

perfectly colourless. B previously weighing the proportions of soli ingredients, the quantity of the salt in soh tion will be indicated; and as it is extremel soluble, it may be prepared so that eac solution becomes

fluid drachm will contain

a

drachm of th

hydriodate. The theory of the decomposition may b thus explained :Five atoms of water are decomposed ; th hydras (the potassa fusa of the former Phar- five atoms of hydrogen unite with five c macopoeia) as will render the mixture almost iodine; this, again, with five of potass, t colourless, and add as much distilled water form five atoms of hydriodate of potass as will make, together, say, two fluid ounces. aad the five atoms of oxygen unite with on The chemical equivalents of the iodine of iodine to form one of iodic acid, whict and potassa would of course be the proper again, unites with one of potass, to fort proportions, provided they could be obtained the iodate of potass ; thus :-

I have not found that the small quantity of iodate of potass formed any objection to its medicinal application. Yours respectfully, WM. NICHOLS, M.R.C.S. Queen-street, Edgware-road,

August 8, 1839. REMARKS ON THE CIRCULATING the carbonic acid gas contained in their in. SYSTEM. terior ; and that the arterial blood, thus formed, is then returned in the course of the To the Editoi, of THE LANCET. circulation, and in this state arrives at and

SIR:—Having read with much pleasure in THE LANCET, for August 10, an analysis of Professor Schultz’s new work on the circulation, &c., I beg to offer a few remarks in connection with the same subject, for insertion in your next number. Dr. Schultz, it appears, has arrived at the conclusion that « there are but two organised elements in the livingblood, viz., the plasma and the vesicles of the blood;" " that the vesicles of the blood, in their perfect state, are composed of a membranous covering, the interior of which is filled with an aeriform liquid, in the midst of which is found the nucleus ;" and " that in respiration the vesicles of the blood absorb oxygen, and preserve it in their interior; while the excitement of the vesicular membrane, producing a contraction of the vesicles, drives off the carbonic acid which was produced by the elaboration of the nuclei by means of the

enters the true capillaries, during its passage through which, the free carbon and oxygen m the vesicles (it must be inferred) conibine to form carbonic acid gas, the blood at the same time assuming the venous cha-

contained

racter. But here it may be

asked, What is the of this phenomenon? What is the agency by which this formation of carbonic acid gas must be determined ? Does it exist? Can it be discovered? As these questions, among others, have been already considered by me in a pamphlet, lately published, I felt interested to examine as to the tendency of Dr. Schultz’s researches in this respect. Judging from the analysis given in THE LANCET, it does not appear that he has touched specifically upon the problem; but his results are by no means opposed to my own conclusions; while, on the contrary, some of his facts seem to narrow the grounds and strengthen the elements of the inquiry. oxygen." Now, in conformity with these views the Dr. Schultz says that the vesicles of the rationale of respiration must, I suppose, blood are the « true respiratory organs," and amount to this :-That on the arrival of the that they " do not quit the vascular canals," venous blood at the surface of the lungs, its * By J. Butler, 4, St. Thomas’s-street, vesicles, distended with carbonic acid gas, absorb oxygen gas, and contract and expel Southwark. cause

795

plasma, as " the true nutritive portion of the blood, by penetrat- DEFENCE OF DR. BUCHANAN’S ing through the parietes of the vessels to APPOINTMENT AT GLASGOW. the parenchyma of the organs," is that " from which all the organs of the body are To the Editor 0/’ THE LANCET. formed and nourished." Now, if this be SIR:—I observe in your No. of the 3rd true, it becomes clear, there can no longer be inst. a letter containing unfair reflections on any doubt, that the agency involved in the the appointment of my friend Dr. Buchanan combination of the carbonic elements of the

whilst the and plastic

blood and the oxygen of the air can have no direct connection with nutrition or organic secernment. Of this, indeed, I had myself no doubt, nor did I find it necessary to make any question of it; the conclusion, however, it must be acknowledged, still fell short of being established on the more positive evidence which I am glad to see thus supplied by the researches of an accomplished phy-

to the chair of Institute of Medicine in

the

Uneversity of Glasgow. Had you been aware of all the circumstances of the case I am sure you would not have inserted that letter without comment. I do not know if I can say the same of the treacherous journilest who inserted in his " Gazette " an elaborate paper of Dr. Buchanan’s and to show his

regard for his correspondent put

into the No. an untrue and ex-parte statesiologist. ment to do him an injury. You are perhaps Beyond the question as to the existence of not aware that you are involving yourself in a particular agency to determine the combia warefare which has been raging in the nation of the free carbon and oxygen (connewspapers for the last fortnight, tained in the vesicles) of the arterial blood, Glasgow with a vindicitive fury and 11 sodium medito form the carbonic acid gas (contained in cum" so genuine as has at once diverted the vesicles) of the venous blood, if the and all the people in the city and disgusted cause of the phenomenon be in reality that the medical part of them. " Musa especially which I have been led to point out, perhaps, mihi causas memora." On this subiect also, that agency might be found to have their can be no doubt. There are few medino small connection with what Dr. Schultz cal men in Glasgow who require to be in. terms " the contractility and vital energy of formed that the author of the whole affray the vesicular membranes," which, also, he is a ° Learned Oculist"who being himself savs. are " verv elastic :’ How far the exa Lecturer in the University very naturally pansion and contraction of the membranes wishes to establish the doctrine that all may be due to vital or mechanical causes; or good things in the University should be first to both (if this be possible), need not here offered to the Lecturers. He has indulged be determined ; but admitting the fact apart in similer grumblings with respect to every from its causes, Dr. Schultz, it will be seen, appointment that has taken does not go, in this direction, beyond the professional in Glasgow for many years past but place " contractility of the vesicle," to account he has been enabled to give free vent to his for any phenomenon in health or disease. I on this occasion under the pretence have attempted to make a step in advance ; feelings of pleading the cause of a friend. But I and I may add that it is somewhat remark- can assure him that his disguise has imposed able, at least, that Dr. Schultz has been led upon none who know him. To give you a to ascribe to his ultimate fact-" the conspeciemen of the unfair dealing of this gentractility of the vesicles "—effects which I tleman and his emessaries, they tell us that have also connected with mine ; and thus, in the number of Dr. Rainy’s pupils has instating his pathological views, he ascribes creased in a most wonderful manner during to the " loss of the contractility of the vesi- the six years he has lectured, and this cles," precisely the same morbid changes in ascribe to the unparalled eloquence of Dr. the blood, the results of which I have referNow they forget to tell that during red to diminished action of the organic Rainy. the same six years the number of graduates function to which, possibly, his ultimate fact at Glasgow has increased in an equal ratio, may be attributable. For as he has thought so that there were last year no less than 130. it possible that all the symptoms in Asiatic every graduate is obliged to attend cholera « may be only the effects of this Now, the class of the Institue of Medicine, for I have been state of the blood so ;" paralytic while Materia Medica or may be led to ascribe the same state of the blood- had elswere the InstitueMidwifery of Medicine can the same disease-to partial paralysis or sus- be had only in Scotland and therefore all pension of function of the superior organic the students go to Dr. Rainy. This the faculty on which, as I conceive, both this other proffessors know to their cost. The vesicular contractility, if it exist, and all Professor of Botany hasa similar advantage other phenomena traceable to it, may be from a ditfrentcause, and last year although found to depend. I am, Sir, your obedient he had no less than 100 students attending servant, his winter course. No man has a greater W. BATTEN. respect for Sir William Hooker than I have but the very name of a Winter Course of 144, Tooley-street, Borough, Botany must convince every man that there August 16,1839. very

same

they