In the Medical Gazette of last Friday, an announcement was made by Mr. Brittan of the very important discovery, that peculiar microscopic objects exist constantly in the characteristic ‘‘rice-water’’ discharges of persons affected with Malignant Cholera, and in the atmosphere of infected places. At a time when cholera is destroying hundreds of our fellow-creatures daily, and filling the land with mourning, it is the duty of every one who believes himself to be in possession of any observations which throw the smallest light on the cause of, and the means of controlling, such an awful visitation, to give them, without delay, all the publicity possible. I therefore venture to submit to the medical profession, and the public, the following remarks. The peculiar objects in question were first seen by two or three members of a committee appointed by the Bristol Medico-Chirurgical Society for the microscopic observation of subjects connected with cholera. The first drawings of them, together with the great variety of other objects, generally to be met with in the ‘‘rice-water’’ discharges, were made by Mr. J. G. Swayne and Mr. F. Brittan, in the second week of July last. These drawings, together with specimens of ‘‘rice-water,’’ were exhibited at the next meeting of the committee. At that meeting there were present Mr. J. G. Swayne, Mr. F. Brittan, Dr. Bernard, Mr. Neeld, Mr. A. Prichard, and myself. Numerous other drawings of the same kind, by Mr. J. G. Swayne and Mr. Brittan, were laid, shortly afterwards, before the Bristol MedicoChirurgical Society. The laborious observations subsequently made by Mr. Brittan and Mr. Swayne, and laid, from time to time, without reservation, before the Bristol MedicoChirurgical Society — though not enforced by any arguments to that effect — certainly did much to show that some very important relation existed between these bodies and malignant cholera. The presumption thus raised was much strengthened by the important discovery, subsequently made by Mr. Brittan, and reserved for separate publication, of the constant presence of objects of the same kind in the air of infected places. Shortly afterwards, and being at the time aware of this discovery, I detected the same organisms in great numbers in almost every specimen of drinking-water which I was enabled to obtain from Cholera-districts. First, in the drinking-water from Wellington Court, Red-cross Street, where cholera first broke out (with any violence) in Bristol; subsequently, in the water of the Float, and in the drinking-water from King Street, in the same city; since then, again, in London, in water from Lovegrove Street, and from the Surrey Canal; and lastly, in drinking-water from the Stapleton workhouse;—being all places where, at the time the water was obtained, cholera was making dreadful havoc. This led me to examine a great number of specimens of water from healthy quarters; and although I often found in it a good deal of matter of various kinds, organic and other, in no single instance did I see anything resembling the peculiar bodies in question. These are certainly facts of great interest and importance, and it is impossible to witness them without being filled with an earnest desire to discover, if possible, their real import and significance. What is the nature of the relation which these bodies bear to Cholera; and may we not have detected in them the actual cause of the disease; are questions which at once suggest themselves to the mind. In endeavouring to obtain for myself an answer to these questions, I have been led by the facts already mentioned, and by others, which will appear in the sequel to the following deductions, which it must be left for future experience and research to confirm or otherwise:—