Fevers. cause. ctrine less enough when merely brought forward as a specula- ORDER I. tion. But it has not always been limited to this point; Pyrectica. for it has occasionally been advanced as a practical and Proximate efficient principle; and the febrile commotion, and particularly the hot fit, has, in treating the disease, been of concoepurposely increased, with a view of assisting nature in tion. her curious but unknown process of expelling the peccant material; and the most dangerous consequences have followed. I. Doctrine in the blood or doctrine haave. II. The acute and penetrating mind of Boerhaave, who II. Lentor was born in 1668, was sufficiently sensible of this danger; and the discoveries which were now taking place in che- of Boermistry and physiology, led him progressively to the construction of a new theory, which in a few years became so popular as to obtain a complete triumph over that of the Greek Schools. derived. Leeuwenhoeck, by a delicate and indefatigable appli- Whence cation of the microscope to animals of a transparent skin, had endeavoured to establish it as a fact that the constituent principles of the blood consist of globular corpuscles; but that these corpuscles differ in size in a regular descending series according to the constituent principles themselves; and that each set of principles has its peculiar blood-vessels, possessing a diameter just large enough to admit the globules that belong to it, and consequently incapable, without force, of allowing an entrance of those of a larger magnitude; and hence that the blood-vessels possess a descending series as well as the particles of the blood. It was upon this supposed fact that Boerhaave built How aphis hypothesis. He conceived that almost all diseases plied. may be resolved into an introduction of any given series of particles of blood into a series of vessels to which they do not properly belong; and he distinguished such in troduction by the name of error loci. He conceived still Error loci farther, that this heterogeneous admixture is very fre- what. quently taking place; and that its chief cause consists in a disproportion of one or more sets of the sanguineous principles to the rest, by which their globular form is Pyrectica. Fevers. Proximate cause. II. Lentor ORDER I. Occasionally broken down or agglutinated; and hence rendered either too thin and serous, or too gross and viscid. The viscidity of the blood he distinguished by the name of LENTOR; and to a prevalence of this lentor, or viscidity, in the blood. he ascribed the existence of fever; maintaining that the general disturbance which constitutes fever proceeds from an ERROR LOCI of the viscid blood, whose grosser corpuscles, from their undue momentum as well as superabundance, press forcibly into improper series of vessels, and stagnate in the extremities of the capillaries, whence the origin of the cold stage, and consequently of the stages that succeed it, to which the cold stage gives rise *; and hence those medicines which were supposed capable of dissolving that tenacity, or breaking down the coalescence of such a state of the blood, were denominated DILUENTS, HUMECTANTS, and ATTENUANTS, whilst those of an opposite character were called INSPISSANTS: terms which have descended to our own day, and are still retained even by those who pay little attention to the hypothesis that gave them birth. Medical nomenclature hence influenced. An elective system com bining parts of many others. Fact in favour of the hypothesis. The system of Boerhaave, therefore, consisted of an elegant and artful combination of both the earlier and later doctrines of corpuscular physiology. Without deserting the humoral temperaments of Galen, or the constituent elements and elective attractions of the alchemists, he availed himself of the favourite notions of the corpuscular pathologists, their points or stimuli, their frictions, angles, and spherules, derived from the Cartesian philosophy, which was now exercising as triumphant a sway over the animal as over the material system; and interwove the whole into an eclectic scheme, so plausible and conciliatory to all parties, that all parties insensibly felt themselves at home upon it, and adopted it with a ready assent. In the emphatic language of M. Quesnay, it was LA MEDICINE COLLECTIVE". The most triumphant fact in favour of the Boer Aph. 756. Comment Van Swiet. Tom. 11. p. 528. Edit. Lugd. Bat. 40. ORDER I. Fevers. cause. but un haavian hypothesis is, that the crust on the blood in inflammations, and cauma or inflammatory fever is often rectica. found peculiarly dense. But as fevers (and certainly Proximate the greater number) are found without any such crust; and as a similar crust, though perhaps, not quite so available. dense, exists under other and very different states of body, as in pregnancy and scurvy (porphyra), even this leading appeal has long lost its power of conviction: whilst the abruptness with which fevers make their assault, from sudden occasional causes and in constitutions of every diversity, forbid the supposition that in such cases a lentor or sizy crasis of the blood, and especially a glutinosum spontaneum can have time to be produced, however it may exist occasionally, and be, perhaps, the source of other disorders. The subject, however, has of late been again taken up by Dr. Stoker of Dublin, with a view of reviving the humoral pathology in its more important doctrines, and of extending the arguments which have hitherto been urged in its favour*. III. To the period of Boerhaave in the production of fever and indeed of all other diseases, the human body was regarded as almost entirely passive, a mere organic machine, operated indeed upon by some AUTOCRATEIA, as NATURE, or a VIS MEDICATRIX, but in the same manner as other machines, and mostly by similar laws. Its muscles were contemplated as mechanical levers, and its vessels as hydraulic tubes, whose powers were calculated upon the common principles of mechanics and hydronamics; and were only supposed to be interfered with by the internal changes perpetually taking place in the fluids they had to convey. A new era, however, at length began to dawn upon the world: a more comprehensive spirit to pervade medical study: the animal frame was allowed to exhibit pretensions superior to the inanimate, and not only to be governed by powers of its own, but by powers which are continually and systematically from a given point operating to a preservation of health where VOL. II. Pathological Observations, &c. Dublin, 8vo. 1823. E III. Spasm treme ves of the ex sels, or doc trine of Stahl, Hoffman, and Cullen. ORD ER I. Proximate cause. III. Spasm of the ex treme ves sels. progress of Followed up and improved by Hoffman. Hoffman's hypothesis how distinguished from Stahl's. Ingenuousness of Boerhaave. it exists, and to a restoration of health where it has been lost or injured. Stahl, who was contemporary with Boerhaave, and in the university of Halle in 1694, first started this loftier and more luminous idea,-more luminous, though the light was still struggling with darkness; made the mind the controlling principle, and the solidum vivum, or nervous system, the means by which it acted. Fever, on his hypothesis, consisted in a constrictive or tonic spasm, in his own language spasmus tonicus, produced by a torpor or inertness of the brain, at the extremity of the nerves, and counteracted by the remedial exertions of the mind, the vires medicatrices of his hypothesis, labouring to throw off the assailing power; whence the general struggle and commotion by which the febrile paroxysm is characterised. Hoffman, who was a colleague of Stahl, took advantage of this new view; followed up the crude and primary ideas of Stahl with much patient and laborious investigation; and soon presented to the world a more correct system, in a more attractive style; but apparently with a disingenuous concealment of the source from which he had borrowed his first hints. He omitted the metaphysical part of the Stahlian hypothesis; took from the mind the conservative and remedial power over the different organs with which Stahl had so absurdly endowed it; seated this power as a law of life in the general organization; separated the nervous from the muscular fibres, the latter of which were regarded as only the extremities of the former by Stahl; allowed a wider range and longer term to the constrictive spasm of fever; and changed its name from spasmus tonicus to spasmus periphericus*: giving also to the moving power of the muscular or irritable fibres the name of vis insita, as that of the nervous fibre was called vis nervea. It is highly to the credit of Boerhaave that his mind, in the latter part of his life, was so fully open to the merits * Med. Nat. Systemat. Tom. III. § 1. cap. 4. Bochmer, Diss. de Spasmi Peripherici signo in febribus continentibus. Hal. 1765. ORDER I. Pyrectica. cause. III. Spasm of the ex treme ves of this hypothesis, that he admitted the agency of the nervous power, though a doctrine that struck at the root of his own system, of which we have a clear proof in the Proximate change which occurs in the fourth edition of his Aphorisms, and particularly aphorism 755, where he lays down the proximate cause of intermitting fevers. Hitherto it had run thus "unde post accuratum examen totius historiæ intermittentium causa proxima constituitur viscositas liquidi arteriosi." But to this, in the edition before us, is added the following: "forte et nervosi (liquidi) tam cerebri, quam cerebelli cordi destinati, inertia."* 1 sels. ness of It is also equally creditable to the learned Gaubius, Ingenuousthat, though strongly attached to the Boerhaavian school Gaubius. in which he was educated, and a zealous contender for mány of its doctrines, his understanding was alike open to the clearer and simpler views of the chemists of the day, upon various points not yet generally adopted, and allowed him to become a more thorough convert to their philosophy. The reader may judge of this change in his mind by the following passage: "An et naturæ humanæ facultas inest, moleculas, acris detritas aut intropressas angulis, in sphærulas tornando, blanditium creandi? Non satis constat speciosam ideam æqualiter in fluidam solidamque acrimoniam quadrare.-Credibilius profectò mixtione chemica magis quam mechanica rotundatione, id opus perfici." In effect, there not only was at this time, but had been for many years antecedently, a general feeling among the cultivators of medicine, that neither the laws of animal chemistry nor of the living fibre had been sufficiently studied for the purposes of a correct pathology: in proof of which it may be sufficient to refer to various articles on both subjects, inserted in the Ephemerides Naturæ Curiosorum, published at Frankfort, in 1684; and the writings of Baglivi‡, and Dr. Baglivi, Willis§; and still more particularly to Dr. Gilchrist's Gilchrist. elaborate treatise on nervous fevers, inserted in the Edin * De Motû Tonico. Theoria Medica vera. Halle 1734. Pathol. § 298-300. Specimen de Fibra Motrici et Morboso. Pathologia Cerebri et Nervorum. General in clination to the same views long in previous existence. Willis, |