Scientific Memoirs by

or non-pathogenous according to circumstances; and a chief discrepancy
revealed in the present research as needing elucidation, is, I consider, the strik-
ing separation of virus and symptoms shown in the cases detailed. That a
plentiful monad-infection should give rise to pronounced, and possibly periodic,
disturbance of the system, is sufficiently comprehensible; and it was the partial
disconnection of the phenomena, which seemed to be obscure,—see especially
case No. 5. The explanation suggested of the trichomonous anomaly was that
the organism of the rat has different properties from that of the horse or mule;
possessing, that is without change of aspect, a biological diversity, such as can
be demonstrated to arise in the bacillus of anthrax under certain conditions of
growth. The fact of such occult change in properties being possible, however
interpreted, warrants the inference that sometimes, e.g., in ague, the parasite
may within the same host undergo beneficial modifications; then under certain
intervening condition alone giving rise to fever, whilst, in general, operating as a
more or less wasting agency. This question is, I consider, not one of a mere
co-temporary junction of phenomena; for if intervening conditions be thus effec-
tive (direct destruction of blood-organisms by drugs being impracticable), the
attempt to cure ‘malarial fever’ might be made through means of them; and,
in point of fact, I have shown that quinine does operate in such way, arresting
pyrexia at once without immediately eradicating the organisms; or even without
preventing their continued development, until after an interval of time long
enough to prove its comparatively slow and indirect influence on their growth.
Upon trial, Fowler’s solution of arsenic proved inefficacious in either arresting
fever (case No. 1), or destroying the parasite (No. 5).

     Amongst the conditions unfavourable to persistence of organisms, may be the
more pronounced pyrexial state belonging to the infection, e.g., a body tempera-
ture of 104° F. (40° C.), as was indicated during the quartan paroxysms of case
No. 1, also during the intercurrent paroxysms of No. 3; in No. 2, however, or-
ganisms were not lessened at 103° F., nor were they numerous during an abortive
recurrence with low temperature in No. 1: in none of these instances had quinine
yet been given.

     Doubtless the visible blood-contamination may naturally subside, though
under what conditions and if at definite periods, has yet to be ascertained;
latency or apparent disappearance of organisms from the general circulation
does not, it seems, imply their entire absence; for remnants, or germs, persist
in the splenic pulp-cells (Laveran and Metschnikoff), which it is conceived may,
by after development or increase, either spontaneous or incidentally aroused,
give rise to renewed outward manifestations, either hæmatic or systemic.

     The modus operandi of organisms in either fever-production or self-limita-
tion, remains as little known here as in other acute specific infections: my
enquiries were not directed towards the subject of ptomaines, or virulent meta-