In a world not scientifically trained, “scientific” theories find popular longevity. The theory in question here is that the U.S.S. Cyclops blew apart from a mixture of coal dust and manganese oxide. This theory has been perpetually recited in any regurgitation of the Cyclops saga for the last 80 years. In light of this, it is ironic that it is the least tenable theory. The US Navy dropped it, to their credit, in only a few days. They had several advantages which popular writers and debunking newspaper accounts did not and still do not have.
On May 7, 1918, Richard B. Levering, of the Department of Justice (FBI), sent a letter to Captain Edward McCauley, head of ONI’s investigation. This letter puts it all clearly, and it is best to quote it in toto.
Dear Captain McCauley
In going about the investigation of the loss of the Cyclops upon the theory which is chemically sound, suggested by Lt. Commander Wilkinson’s office, that the cargo of manganese dioxide would be highly incendiary when mixed with some of the material which we are working with, hexamethylene tetramine, I secured samples of the actual ore, as it is being shipped from Rio on these ships.
The laboratory reports to me today that it is exceedingly unlikely that sufficiently ideal conditions could have been created to cause any great incendiary effect with hexamethylene tetramine, and they advised me that they consider this particular theory of her destruction as almost untenable.
However, in working with the material, similar to the Cyclops’ cargo, they have come upon what appears to be a very much more practical suggestion. This ore is an extremely oxidizing agent, and that a mixture of this material with coal dust forms a highly inflammable compound. Inasmuch as this ship was a collier, it is possible that no great care was taken in cleaning her out before taking on the cargo of manganese dioxide, and there might have been sufficient coal dust accumulated in her storage spaces to have made the combustible combination.
They report to me that a mixture of coal dust and manganese dioxide can be set on fire very easily.
I have arranged for a very thorough investigation of the conditions attending the loading of this ore at Rio, as the underwriters of vessels here inform me that the manganese cargoes have proved very troublesome from many aspects to all of the ships which were in this trade, and that there is good ground for watching the situation.
I have arranged for the cooperation of Mr. H. E. Inman, who is Lloyd’s executive officer at Rio de Janeiro, who will give us the benefit of the service of several of his inspectors who may be relied upon. We have an additional arrangement with the representative of the oil company at Rio.
I am sending a copy of this report to Mr. Bielaski, and would appreciate very much if you would give me any information you have bearing on the question of how thoroughly the coal compartments of the Cyclops were cleaned out before loading the manganese ore.
Yours very truly,
McCauley wrote back on May 10, two days after receiving the letter, and it is reproduced here.
Personal & Confidential
My dear Mr. Levering,
I am in receipt of your letter dated May 7, 1918, in regard to the results of your investigations into the loss of the Cyclops.
The Navy Department has accurate figures showing the amount of coal on hand at the time of loading manganese in the amount taken on board subsequently. And for that there is a suspicion in your mind that coal may have been left in the bunkers and covered with manganese, the result being a combustible combination. This theory, however, is untenable, due to the fact that the cargo was not stored in the bunkers but in the regular cargo space.
I shall be pleased to receive any information obtained by you in the course of your investigations, especially any details which may lead to a plausible conclusion regarding the loss of the Cyclops.
Thanking you for your cooperation, I am,
Very truly yours,
Edward McCauley Jr.
Levering wrote back on May 14, 1918,
Department of Justice
PRIVATE & CONFIDENTIAL
Dear Captain McCauley
I have received your letter of May 10, and will certainly keep in touch with any matter that appears to be of any importance whatever in connection with the investigation of the loss of the Cyclops.
I’ve written to call attention to one matter in your letter however, concerning the unlikelihood of the theory of coal dust having gotten mixed with the manganese dioxide. My thought was not that the ore got mixed with the bunker coal, but from the diagram which Lt. Grimes gave me, it seemed possible that if the Cyclops had been carrying a cargo of coal just before the cargo of manganese, that her cargo space might have contained coal dust remaining from the previous service, and that this dust in the cargo space itself might have become mixed with the manganese dioxide, and in that manner formed an inflammable combination.
We will drop this theory from the investigation as suggested by you. I merely emphasized this once more as our laboratory feels that in the future any ship which has carried coal should be carefully cleaned before loading manganese dioxide in the same space.
Very sincerely yours,
McCauley’s skepticism was not doubt indicative of his knowledge of Richard O. Momsen’s long letter to Chief of Naval Operations regarding how the Cyclops was loaded in Rio.
There was actually very little reason for the Navy to suspect coal dust contamination and massive explosion. But this was all Private and Confidential. The press would and still does regurgitate these possibilities. But they were laid to rest by May 15, 1918. They exist today only in the world of popular myth and counter myth, mystery and popular solution. Within this world so much was about to begin brewing and today it is still fermenting.
Amidst all the attempts to rationally explain the disappearance of the huge vessel it is remarkable that the report of solid and identified wreckage remained publicly completely unknown. It was almost 2 years after-the-fact that it was found, but this private and confidential discovery finally gives us some interesting clues as to where and how the Cyclops was lost, and just possibly it may actually resurrect the most sensational theories to account for the “greatest mystery in the annals of the Navy.”