Faraday to Richard Phillips   15 February 1820

Feb 15th 1820

Fresh train oil 3oz in a wedgewoods basin over a charcoal fire at 380° abundant fumes would not burn condensible 430 combustible if confined by a glass plate laid over the basin 470° oil slightly browned - 480° very combustible if confined not when open from dilution by the air - 490° combustible when open: at the surface of the flame flickering about the taper - 530° only a little brown - vapour principally condensible - 560° flame at the surface continues a few moments - 600° Mercury boiled out barely boiled immediately after oil boiled - flame of course continuous[.]

On cooling it would scarcely burn when open at 530° and scarcely when closed at 480°

Other experiments gave similar results[.]

Placed train oil in a retort and the retort in an oil bath - heated up to 580° but no permanently elastic inflammable gas liberated - all the vapour condensible - removed the bath & heated by naked fire - on boiling the oil distilled and permanently elastic gas was liberated it was received over water. It burnt with a pale blue flame and remained some time in inverted vessels distilled to dryness gas continued coming over pretty equally the whole time[.]

Weight of the vapour of oil easily observed by boiling in a florence flask.

4oz of train oil in a glass retort distilled with moderate rapidity obtained 3.75oz having condensed the vapour only in a flask placed in water. When the fluid was cold its combustibility much greater than that of common oil[.] When heated in a basin it burnt readily at the surface at 300° and at 490° it boiled. The quantity made up to 4oz by adding oil that had been once distilled and this redistilled as before[.] A volatile naptha like fluid came over at first with a little water but this was not separated[.] The products being received all together[.] The fluid was not distilled quite to dryness a black tarry matter remained in the retort and the condensed part was not much colored[.] The quantity collected amounted to 3.6oz. When cold it was so combustible that a light applied to its surface inflamed it and it went on burning vigourously[.] When heated it rapidly formed vapour and boiled at 210° burning violently if a light was applied to it[.] As the Naptha passed off the boiling point heightened till it reached 400° when about half the fluid had evaporated.

2oz of oil twice distilled were again distilled and the products received in 5 different portions[.] At first Naptha came over with a little water (the water being formed from the oil apparently) and its quantity was about one tenth of the whole (this you saw the other day in Lombard Street)[.] Then the other portions more & more fixed till a substance like tar remained in the retort[.] On cooling Nos 1 & 2 remained clear and perfectly fluid[.] Nos 3 & 4 had a crystalline or flakey diposition in them which in the small quantities I have examined appears to be the new substance lately spoken of as the base of charcoal[.] No 5 the tar was a little thicker than before[.] Nos 1, 2 & 3 were of a bright yellow tint No 4 a little discoloured & No 5 black. The quantities of each were nearly as follows the whole quantity collected being 13.3.

Some recent train oil put into a florence flask was heated at temperatures and at intervals for 24 hours from 350 to the boiling point about half of the oil had disappeared in that time from loss by evaporation. When cold it was very thick and brown like tar but became fluid immediately on being heated - Heated in a wedgewoods basin vapour soon ascended[.] It began to burn by applying a light at its surface at 320° - at 380° it burnt continuously for a few moments - at 410° it burnt freely at the surface - at 450 very difficult to blow out though but a small surface exposed at 470 began to boil at 520° boiled freely and when a light came near burnt with a strong flame.

Dear Phillips - I have read yours & send you the above notes[.] I have set an experiment going in which recent train oil is heated in a flask with a long tube attached to it Mattress fashion to temperatures not above 400° but between that & 370°[.] The heat has now been applied about 8 hours & there is already appearances in the tube like moistening by Naptha[.] I intend to have it at this heat for a long time & then ascertain the changes of the oil¹.

Cooper called on me this morning². He came to me before I had been engaged by the fire office and asked me about oil and I had told him that an inflammable vapour rose from oil at 340°. This morning he cited his experiments to me in which he had not been able to get an inflammable vapour under 580° !!! and I expect he will advance some such thing in court[.] His oil was recent & his apparatus a close one with the orifice I suspect much colder than the body. Pray see that I am correct and the moment you can let me know your results

Yours Very Sincerely | M. Faraday

Feby 15th 1820

I shall send a copy of these notes to Messrs Millington³ & Taylor⁴ & hope they will find them accord with their experiments.

Address: R. Phillips Esq | Royal Military College | Sandhurst