Still more recently, and due, no doubt, to a great extent to the work of Elschnig, further attention has been drawn to the vascular system in lead poisoning. Elschnig’s work has carried the question another stage forward by showing the association of vaso-motor disturbances with eye disease, whilst in this country Oliver[75] pointed out the effect upon the pulse of abdominal colic. At the beginning of the researches on this point described in the next chapter, this clue running through the whole of the pathology of lead poisoning was not appreciated. At the commencement of the investigations there seemed to be no main general line of symptoms or histological findings that could be adduced as characteristic of lead poisoning; in fact, the initial experiments were performed, with the object of examining the association of lung-absorbed lead compounds as a possible cause of lead poisoning, as against the entrance of lead by the alimentary canal; but as the experiments proceeded it became clear that the stress of the initial intoxication was undoubtedly falling upon the bloodvessels, and more particularly upon the minuter bloodvessels, and less on the arterial side of the capillaries (although the capillaries were to a large extent associated with the process) than upon the venous radicles. A general consideration of the pathology shows that lead causes changes in the nervous system affecting both upper and lower segments, degeneration of the ganglion cells in the cord and in the brain, interstitial inflammation of the neuroglia, cortical degeneration, distinct neuritis, both axial and peri-axial, of the peripheral nerves, and also signs of change in the sympathetic nervous system in chronic lead poisoning. Later work has, however, all tended to point out that the chief and first effect of lead is upon the blood. Moritz[76] first pointed out the presence of basophile granules in the red blood-cells. The work was followed up by Emden[77], Gravitz[78], Zinn[79], Otto[80], Silbert[81], and by Escherich[82]. All these authors found basophilic erythrocytes in the blood associated with blood-destruction, and Escherich in addition describes early changes taking place in the intima of the bloodvessels associated with vaso-constriction. The Italian author Mattirolo[83], as well as Marchet[84] and Jores[85], came to a similar conclusion. Glibert of Brussels[86], carrying the observations somewhat farther, and although working with guinea-pigs, which normally show basophilic staining in their blood-cells, was able to demonstrate one further point of considerable value--namely, the increase in the viscosity of the blood, with blood-corpuscles of greater toughness, elasticity, and power to resist destruction when making films, than in normal blood.