5G0 DU. CHISHOLM ON THE MALIS DllACUNCULUS. 
attacked by the disease, whilst the inhabitants at the distance of only 
half a mile, who drink water from another well , are not exposed to 
it; or how it happens that those living on the shores of the Cavary, 
and other rivers, who constantly drink their limpid waters, are 
never visited by it; whilst those who live at a distance of one 
mile on both sides, and are obliged to drink the saltish water of 
wells , are all , or the most part , yearly exposed to it. Dr. Ander- 
son, although desirous of maintaining the admission of the worm 
by the skin, cannot get rid of M. Dubois's powerful fact. “ Nor 
can we cavil," says he, “with the idea of an entrance by the 
chylopoetic organs, when we see worms in the eyes of horses 
and the livers of sheep." ( Edinburgh Medical and Surgical 
Journal, vol. ii, p. 301, 305). Dr. Anderson afterwards re- 
marks a very singular circumstance in the history of dracunculus, 
which perfectly corresponds with my own observation at Gre- 
nada, and with that of others at Bombay. Your notice of wells 
of saltish water, where the guinea-worm is most frequent with 
you, renders it in some degree probable that vitriolic and marine 
salts, which are found both in the wells and in the sea, are not 
unfavourable to their propagation. 
But setting aside these disproving facts, if they may be so 
considered, respecting the contagious nature of draunculi, it is 
evident that the “ exanthemata viva" can in no instance be in- 
fectious in the manner supposed to have happened in the 88th 
regiment. “ Insecta ejusmodi minutissima forte acaros divers® 
speciei, causas esse diversorum morborum contagiosorum, ab 
analogia et experientia, hactenus acquisita, facili credimus ne- 
gotio ; neque repugnat horum structura et magnitudo ; minima 
enim sunt animalcula quae oculius humanus adhuc percipere 
potuit. Ex sensibus agitur, ad rei impossibilitatem non est 
argurnentandum ; eeque enim in minimis ac maximis sapien- 
tissimi conditoris artificium elucet." (Amcenit. Academ., tom. v, 
P-94.) 
In this learned and interesting discussion, the author employs 
the words contagion and contagious in their literal and legitimate 
meaning, as they are derived from the verb contingo , and not in 
the figurative sense in which they are generally applied. By 
contact, then, colonies of minute insects may emigrate to and 
form establishments on a healthy person from a diseased one. 
But such colonizations are confined to insects of the acarus 
kind ; and in all the diseases which the writer of the Exanthe- 
mata Viva attributes to the agency of insects, different species 
of the acarus are alone the cause. The nature of dracunculus 
is inconsistent with this mode of propagation, more especially 
under the circumstances the soldiers of the 88th regiment arc 
