_De eodem, tamen alio modo._ Annis Arabum 630 transactis, petitioni tuæ respondeo in hunc modum.... Item pondus totum 30. Sed tamen salis petræ[370] LURU VOPO VIR CAN UTRIET sulphuris; et sic facies tonitruum et coriscationem, si scias artificium. Videas tamen utrum loquor œnigmatate aut secundum veritatem. Omitting the anagram, the translation is:—“In this 630th year of the Higira I comply with your request as follows.... Let the total weight (of the ingredients) be 30. However, of saltpetre ... of sulphur; and with such a mixture you will produce a bright flash and a thundering noise, if you know ‘the trick.’ You may find (by actual experiment) whether I am writing riddles to you or the plain truth.” The mention of the flash and the noise indicates at once that we have here to do with an explosive. But saltpetre and sulphur when mixed together do not form an explosive. We may feel sure, therefore, that the name of the one substance necessary to convert the incendiary mixture of saltpetre and sulphur into an explosive, namely charcoal, is included under some form in the anagram—either as _carbo_, or the name of the wood from which it is made. The _et sic facies_ of the second clause shows that there must necessarily be in the first clause, and consequently in the anagram, some verb in the imperative mood, such as _mix_ or _take_. We may expect a word for a weight (_libræ_, _unciæ_, &c.), or the word _partes_. As regards the proportions, the earliest we are acquainted with approximate more or less closely to 2:1:1, Arderne’s recipe being merely a laboratory recipe. The proportions of the ingredients, therefore, if included in the anagram, will probably not differ much from 2:1:1. Rearranging the letters of the anagram, we get— RVIIPARTVNOUCORULVET, or since U and V are interchangeable, R. VII PART. V NOV. CORUL. V ET; _i.e._ r(ecipe) vii part(es), v nov(ellæ)[371] corul (i), v et. The whole passage in the original therefore reads:— “sed tamen salis petræ recipe vii partes, v novellæ coruli, v et sulphuris,” &c.; that is— “but take 7 parts of saltpetre, 5 of young hazel-wood, and 5 of sulphur,” &c.; _i.e._ 1-2/5 sp., 1 char. and 1 sulph. _R._ was the common contraction for _recipe_, and may be seen in Marcus Græcus’ first recipe (Berthelot’s text). _Nov._ _Corul._ could have presented no difficulty to Bacon’s correspondent, seeing that in the previous letter, Cap. X., Bacon had spoken of _virgulti coryli_. There he writes _coryli_: in his _Opus Majus_ he wrote _coruli_ (ii. 219, Bridges ed.). The second anagram (in Greek, Roman, and Anglo-Saxon letters) seems to be a note to the first and need not detain us, since we have already got the names and proportions of the ingredients. In deference to those readers who may reject the preceding attempts to read Bacon’s riddles, we now proceed to show, on grounds independent of the steganogram and anagram, that Bacon was in possession of an explosive.