The Mondones petroleum case (Valladolid, 1585)
A documented Castilian lawsuit in which the medical claims of an imported oil were put to a court. An Italian merchant selling petroleum as medicine was ordered to stop on the ground that it was "fake and false"; two university physicians were appointed to examine the substance and reported on it in writing. The case shows early modern Spain running a real adjudicative procedure over a drug — and shows exactly what that procedure tested, which was the printed authorities and not the patients.
Why this wins its question: Ask what regulated medicines in Habsburg Spain and the answer returned is always the Protomedicato, described as a licensing monopoly, in the abstract. This object answers the question from one fully documented suit of 1585 and gets a different and more useful picture: the medical tribunal was not the venue, the ordinary tax courts were; the evidence that decided it was a royal writ, three earlier sentences, a printed handbill's citations and a two-physician inspection reported in writing on a dated day; and one of the two examiners was the future protomédico of Castile. It records the genuine achievement — an adversarial procedure in which a medical claim was referred to appointed experts and decided on law, two centuries before drug regulation is usually said to begin — and, in the same breath and from the same study, its defect, that what the experts tested was whether the substance matched the books.
Claims
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The case concerns Guido Mondones, an Italian merchant who sold petroleum as a medicine in Spain in the 1580s. The formal question in dispute was fiscal rather than clinical — whether his medicinal oil was subject to the alcabala, the sales tax — but answering it required the courts to determine whether the substance was in fact a medicine.
The venues were the ordinary courts, not the medical tribunal. The matter did not go before the Protomedicato, the Casa de la Contratación or the Council of the Indies. Mondones's royal protective writ issued from the Consejo de la Contaduría Mayor at Madrid, and the litigation ran through the Sala de los Alcaldes de los Hijosdalgo and then the Sala de Oidores at Valladolid.
Mondones litigated on paper and had done so before. He carried copies of favourable sentences from earlier tax disputes at Huete, Corral de Almaguer and Alcázar, all of 1582, together with the royal writ exempting medicines from the ten-per-cent sales tax. By July 1585, when the Valladolid case opened, he had earned "300 ducados, more or less" from two months of sales at Huete.
The claim was challenged and referred to experts. On 29 September 1585 the governor Menén Suárez de Solís ordered Mondones to stop selling, on the ground that the oil was "fake and false", and two physicians were appointed to inspect and evaluate it: licenciado San Pedro, and Doctor Luis Mercado, chair of medicine at the University of Valladolid, who would become protomédico of Castile within seven years. The examiners were therefore of the first rank available.
Their finding, delivered on 2 November 1585, was that Mondones's oil was "the petroleum of which the authors make mention" and showed "no signs of it being adulterated". The test was one of identity and purity, settled by chemical inspection against the description in the printed authorities. No clinical trial was conducted and no patient outcome was in evidence.
The authorities in question were named in Mondones's own advertising handbill, printed at Salamanca in 1584: Andrés de Laguna, physician to Charles V, Pope Julius III and Philip II, and specifically his 1555 translation of Dioscorides; Antonio Musa Brassavola's Examen simplicium; the Circa instans of Matthaeus Platearius; and Pietro Andrea Mattioli, who noted that petroleum springs forth in Modena and other places in Lombardy.
The exemption Mondones invoked was statutory and specific: law 14 of title XVIII of book nine of the Nueva recopilación de las leyes destos reinos, which exempted "ungüentos y emplastos y aceites" — unguents, poultices and oils — from the sales tax.
The American connection runs through the medical literature rather than the cargo. Nicolás Monardes's Historia medicinal de las cosas que se traen de nuestras Indias Occidentales (1565) had helped establish petroleum's medical legitimacy, writing that New World petroleum served for "griefes of the Mother" and "cold Infirmities"; Mattioli, cited on the same handbill, located the substance in Lombardy. The oil actually sold in Castile is not shown by this case to have been American.
The limits of the system are the study's own conclusion and belong on the record with the achievement. Regulation deferred to published authorities rather than to empirical testing; simple substances such as petroleum drew less scrutiny than compound preparations, whose recipes had to be verified; local magistrates exercised wide discretion and generally deferred to royal writs and expert opinion; and there was no centralised testing authority, the Protomedicato being unable to control all medical practice despite its theoretical authority. Mondones prevailed by navigating the bureaucracy and marshalling printed precedent, not by demonstrating that his oil cured anyone.