592 A New Conception of the Glomerular Function. 



to determine from histological evidence the part of the urinary apparatus 

 thrown into activity by the different urine exciting substances. 



[Addendum. — Shortly after I delivered this lecture before the Royal Society, letters 

 appeared in the ' Lancet ' and the ' British Medical Journal ' by Mr. Wm. Woods Smyth, 

 claiming that his brother, Dr. A. W. Smyth, had over 30 years ago anticipated the views 

 I now expressed. Dr. Smyth's views of the function of the kidney appeared in a 

 pamphlet by Mr. J ohn Gamgee, in the ' New Orleans Medical and Surgical Journal ' for 

 May, 1880, and were based upon microscopic examination of the kidney, and upon the 

 fact that the kidney pulsated with each heart-beat. As far as I am aware, no reference 

 to his views has ever appeared in the literature upon the kidney. They concerned the 

 glomerulus and the circulation through the kidney. He denies the existence of any 

 " connection between the capsule of the Malpighian body and the interior of a uriniferous 

 tubule," and also " having observed that the hyaline membrane, enclosing each glomerule, 

 was unprovided with epithelium, essential to every secreting structure, Dr. Smyth 

 perceived that so delicate a sac would rupture, and the plexus be destroyed, if subjected 

 to hydrostatic pressure, either during secretion or from accidental regurgitation." But 

 the main point in relation to this lecture is his view of the mode of working of the 

 glomerulus. This he describes in the following terms : — " Every heart-beat is attended 

 by turgescence of the glomerule. The loops, from their position and form, must swell 

 outward and inward in all directions, and, constricting the efferent vessel, momentarily 

 impede the blood's exit. At each cardiac diastole, the arterial column sustaining the 

 blood in its channel, the Malpighian loops recoil and fill the current in the secreting 

 vascular rete. And this is Dr. Smyth's view of the special function of the Malpighian 

 bodies. Their alternate turgescence constituting a ' rhythmic vascular impulse,' a 

 uniform, safe, and sufficient expelling pressure is maintained on the coiled tubes, and, 

 indeed, on the whole excreting structure of the kidney. Those acquainted with the 

 laws which govern the flow of liquids can readily understand that the power required 

 to maintain a circulation, beyond the coils of the glomerule, would be destroyed, if a 

 mere physical transudation could occur through the loops, so well disposed to bring the 

 very active pulsation to bear on the maintenance of a circulation." 



" The unmistakable constriction of the efferent vessel, on the filling of each glomerule, 

 causes an alternation between clearance of the tubuli and the flow of blood in the 

 secreting vascular rete. The glomerules are filled during the heart's systole ; the 

 secreting rete is turgid during the heart's diastole." 



Undoubtedly Dr. Smyth's conjecture was in the right direction, but his erroneous 

 conclusion that Bowman's capsule did not open into the tubule, and the fact that he 

 ascribed all the expelling power of the glomerulus to its pulsation, will indicate 

 sufficiently the great divergence of his views from those I have expressed in my lecture.] 



DESCRIPTION OF PLATE. 



Fig. 1. — Microphotograph of Cortex of Kidney of Cat, after period of rest, showing 

 absence of lumen in convoluted tubules and irregular outline of glomeruli, 

 x 120. 



Fig. 2. — Microphotograph of Cortex of Kidney of Cat, after sulphate diuresis, showing 

 widely dilated tubules and distended capsules, which are now rounded and 

 contain much fluid. The glomeruli are larger than in the resting kidney, but 

 not filling the capsules, x 120. 



