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" Westminster Medical Society (WMS): Discussion of candles containing arsenic "

(28 October 1837)First mention of Snow in London medical journals.

[N.B. all transcripts concerning the poison-candle caper are grouped together for context, even when JS is not specifically mentioned.

"Westminster Medical Society." Lancet 1 (1837-38): 211-12. Meeting of 28 October 1837, second agenda item: Dr. Scott summarized a presentation on poisonous candles a few months earlier by Mr. Everitt before the Medico-Botanical Society. Mr. Everitt had reported that a new style of candle, apparently popular because of its bright light and low cost, contained by his experiments 4 grains of arsenic per candle. Dr. Scott related to the WMS that he had some contacts with candle manufacturers (who were upset at being forced by the competition into practices they found disturbing), and heard reports that some candles now on the market contained as much as one pound of arsenic to 28 pounds of stearine wax. Moreover, while at first sold mostly to private dwellings, these candles were turning up in churches and would probably soon appear in theaters, increasing the potential public health risk. Dr. Scott solicited the opinion of the WMS upon the situation. The members argued about the form arsenic would assume after being burned in a candle - Dr. Addison claiming that the metal would be rendered innocuous, while others insisted it would appear as arsenious acid and therefore extremely poisonous (211-12). Two speakers alluded to the absence in Britain of any "medical police" who could take any action in the event of incidents like this one, if a threat to the public health were demonstrated. One of the prominent physicians they quoted, who had previously called attention to the need for such an institution - and had been ignored - was Dr. O'Shaughnessy, who had undertaken research on the composition of the blood during the 1832 cholera epidemic.]

"Westminster Medical Society." Lancet 1 (1837-38): 242-44. [Continuation of discussion of arsenical candles: The discussion resumed on Saturday, 4 November 1837, and took an unexpectedly modern twist - a fear of lawsuits. Dr. Scott opened the meeting by stating that some members feared that if the WMS made any statements about poisonous candles, they could be sued for libel by the manufacturers. Accordingly, Dr. Scott had obtained a legal opinion from Sergeant T.N. Talfourd of the (Inner?) Temple, who reassured them that they need not fear legal consequences so long as they acted in good faith and did not single out any manufacturers by name. Thereafter, Everitt commented "that in his experiments on these candles, he had been enabled to detect, unequivocally, the presence of arsenious acid. The quantity he found was about three or four grains in a candle; but experiments might be made by which the quantity would be more accurately detected; for instance, if the fatty portion of the candle were dissolved in sulphuric ether, the arsenious acid would be precipitated, and might be collected" 243). The reporter next noted that "Mr. Phillips and Mr. Snow had succeeded in detecting arsenious acid in these lights" (243) - first mention of Snow's participation in the Society, and first public mention in the medical literature. Other members debated the health consequences of the candles - two who had used them reported no ill effects; two others who had also used them reported ill effects; and another referred the members to the long history of serious health problems seen among workers in arsenic mining and manufacturing. The WMS then formed a select committee to carry out further experiments in consultation with Mr. Phillips and Mr. Everitt; it is unclear if Snow was appointed to this committee. In addition, Mr. Everitt would conduct experiments on sample candles at the 18 November mtg.]

"Westminster Medical Society." Lancet 1 (1837-38): 391. [Meeting of 2 December 1837. Dr. Scott initiated a motion to have a deputation from the WMS meet with the Secretary of State to discuss poisonous candles; motion withdrawn since the Select Committee had yet to report.

"Westminster Medical Society." Lancet 1 (1837-38): 424-28. [The Committee returned its lengthy report on 9 December 1837. Dr. Granville read it in toto, and the Lancet seems to have printed it in full, as well. The Committee had reviewed the history of these candles, noting that some 25 years previously, M. Chevreuil in France had found that common tallow consisted of two distinct substances, stearine and elaine. The stearine was found to have excellent color and consistency for candle-making but was also difficult to work with. But about 6 years previously, some stearine candles were successfully manufactured in Paris by a secret method. Eventually it became generally known by candle manufacturers in England that the "secret" was to mix white arsenic with the stearine. While these candles were becoming more popular in England, under various trade names such as "German wax-lights," "Venetian wax candles," etc., the French authorities had proceeded to outlaw their sale. Both chemical and physiological experiments were conducted by WMS members. The first succeeded in showing that arsenious acid, black oxide of arsenic, and arsenuretted hydrogen could all be given off by these candles depending upon the conditions under which they burned, although only the first was likely under normal conditions. Nonstearine candles were found to contain no arsenic. In the "physiological" experiments, seven bullfinches and linnets gave their lives to science as a result of breathing air in boxes in which the stearine candles were burning; a rabbit appeared ill from the candles; the effect on two guinea-pigs was inconclusive, although they refused to eat corn. Birds and the larger animals in boxes with regular tallow (spermaceti) candles showed no ill effects. The Committee next reviewed medical evidence that humans were adversely affected by the inhalation of these arsenic-containing gases, and calculated that if the Drury Lane theater were lighted with these candles, 608 grains of arsenious acid would be given off during the time of one performance. Their final conclusion was reported as: "the vapour given off from [the candles] during combustion is likely to be prejudicial. In closing their report, the Committee express their wish to be of service to the public in a matter of so much importance, in the absence of all medical police in this kingdom, the only country in Europe where the public health is so little regarded by the governing powers" (427).]

Editorial. Lancet 1 (1837-38): 457-59. ["The question of 'arsenical candles' has been taken up and prosecuted by the Westminster Medical Society, in a manner which is calculated to reflect considerable credit on the members of that body" (457). The editorial went on to review the history of the candles, to cite the "clear proofs (459) from the WMS experiments that even small amounts of arsenic are injurious "to the animal economy," (458) particularly when its vapors are "brought into incessant contact with the lungs,- an organ which is peculiarly liable to disease, and calculated to transmit poisonous substances to the economy with greater rapidity than the stomach, or any other part of the animal frame" (458), and to compare British official indifference unfavorably to the French example of prompt legal intervention. The editors chose to highlight the WMS deliberations "on the important, though, in this country, much neglected, subject of the means of preserving the public health" (457). "Public hygiene is the science which embraces the principles, and explains the methods, which are best calculated to promote or preserve the health of a whole population" (458).]

"Westminster Medical Society." Lancet 1 (1837-38): 461-63. [mtg of 16 December 1837, the last before the Christmas recess. Mr. Golding Bird, who in the Committee report had been unsure if the poison had been inhaled or swallowed, had again tried to recover arsenic from the bodies of the dead birds, and once again, finding only a minute quantity; he could find no trace of arsenic on the feathers. But he had noticed that the birds, before dying, and drunk a considerable quantity of water, and he found that the water in the boxes was contaminated with arsenic. He wondered if the water rather than the air was actually the main route of entry of the poison. The reporter next noted that "Mr. Josh. Toynbee, and Mr. Snow, had conducted a series of experiments on these candles, to ascertain the effects of their combustion on animal life. They found that guinea-pigs, exposed to a constant stream of vapour, from six of these candles [stearine], for two separate periods of eight hours each, were not at all affected, even though the temperature of the box, through which the vapour passed, was occasionally as high as 110°. The animals ate their food, which was constantly exposed to the gas. The experiments were subsequently repeated, and carried on for a period of six days, in a temperature never exceeding 80°, with the same results. Two candles were then made, each contained a drachm of arsenious acid; the vapour from these did not affect the guinea pigs. Subsequent experiments with some birds had been instituted, but owing to the apparatus having ignited, no satisfactory conclusion could be drawn from them; for, though one of the birds perished in the smoke caused by the fire, the other lived for four hours, after drinking with great avidity during that time. The stomach, and commencement of the intestinal tube in each of these birds, were found of a bright red colour" (463). Dr. A. T. Thomson noted that guinea pigs were "the most difficult of all animals to affect with poisons."] Snow and Toynbee devised experiments to attempt to resolve the inconclusive effects on guinea pigs; unclear if they undertook this on their own volition or were asked to do so. Whereas the Committee had not been overly concerned with the temperature - "As a general statement it may be remarked that, with the exception of of the first day, when it varied from eighty to ninety degrees, the temperature of all the boxes was kept, more or less, at the standard of summer heat, as the most congenial to the animals submitted to the experiment . . ." LMG 21 (1837-38): 587 - Snow and Toynbee considered it possible that the amount of arsenical vapours in the atmosphere could be dependent on temperature of ambient air. These experiments are the earliest extant evidence of Snow's interest in respiration and poisonous gases.

"Poisonous candles." LMG 21 (1837-38): 577-80. [editorial of 6 January 1838; arsenical vapors as the latest source of death to inhabitants of London (in addition to "noisome exhalations, from the decomposition of animal and vegetable matter" (577), overcrowding, etc. Gives overview of how the WMS came to deal with the issue after Mr. Everitt first raised it at the Medico-Botanical Society in mid-1837. Also notes that the entire report of the select committee, drawn up by Dr. Granville, "is now before us" (578) and extracts from it published separately later in same issue. Reviews the caper and how it was exposed. Does not include JS amongst those who conducted the experiments. Editorial clearly outlines the experiments and results, as well as the literature search of previous incidents undertaken by the committee. In conclusion, "the thanks of the community are due to the Society for the pains which they have taken in investigating s subject of such importance to the public welfare" (580).]

"Westminster Medical Society. Extracts from the report on arsenicated candles." LMG 21 (1837-38): 585-88. [issue of 6 January 1838. Extensive selection. More understandable than the summation given by the Lancet's reporter.]

"Westminster Medical Society." Lancet 1 (1837-38): 675-76. [A footnote to the report on the 27 January 1838 meeting states that, "The Committee of Management of this Society, and some of the members, are at issue respecting the costs of printing the late Report on Arsenical Candles. The former deny that the members who conducted or aided in the inquiry, had any warrant, under the laws of the Society, for engaging in that expense. The parties who have paid the money demand reimbursement. To night (Feb. 3) a special meeting of the whole Society will be held, and the matter fully discussed. A large attendance is expected. The cost of printing is about £25; the cost of the experiment was also £25, neither of which has yet been paid by the Society" (675).

"Westminster Medical Society." Lancet 1 (1837-38): 722. "At a special meeting held this night [3 February 1838] there was a large attendance of members, the majority of whom supported the Committee, who have refused to receive or pay for the Report on Arsenical Candles, which they say was printed and published contrary to the written laws of the Society."

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