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G & W Dettmer, Pianoforte-makers: a Biographical Timeline 1775 - 1858

(added 17 January 2016)



Founded by George Dettmer towards the close of the eighteenth century and continued by his son William, the house of Dettmer was active in London until 1848, when son William, by then of an age to retire, left England's shores and emigrated to Australia to join members of his family who had already settled there. William continued to be active in the industry as a tuner and instrument repairer in his adopted country until he died there in 1858.

The firm occupied premises at 7, Gresse-street, London from 1799 through to 1809, when William moved to larger premises at 50, Upper Mary-le-bone street, London. George, however, is still to be found in Land Tax records at 13, Gresse-street from 1811 - 1819, next door but one to William Southwell, who was situated at No 11 at that time.

The house of Dettmer became noted for its circular cornered square pianos, of which at least one handsome examples survives, a highly decorated instrument sold at auction by DuMouchelles,Detroit in 2009. The nameboard of this instrument gives the address as 7, Gresse-street, indicating it was made before 1809.

George Dettmer died in Paddington, London in 1833, at the grand old age of 93. His son William died in Sydney, Australia in 1858. William's death notice, placed by his family, gives his age as 85.


To date, the author has been unable to locate the date and place of birth of George Dettmer, patriach of this large family of pianoforte makers; nor has the record of his marriage been identified. However, the record of his burial in the parish register of St. James, Westminster in 1833 gives his age as 93, which suggests a birth year of ca. 1740 (see 1833 below). One may conjecture that George may have been a migrant craftsman who came to London from Germany seeking work, bringing with him his wife, but this remains unproven. A number of children born to the couple have been identified of whom several subsequently became active in the business, most notably William David.


The first positively identifed parish register entry for the family identified by the author is that of the baptism of William David Ditmer (sic) [Dettmer], son of George and Ann on 2 July 1775 at St Pancras Old Church, London (parish register, via

Though William Dettmer's age at the time of his death in Australia in February 1858 is given in two death notices as 85 years, which, if correct, would indicate a birth year of 1773, it is possible that he was not baptised until he was two years old. Children were not always baptised within a few weeks or months of their birth; occasionally one even finds entries in parish registers where parents had several children of different ages baptised in the same ceremony. Since compulsory civil registration was not introduced in the United Kingdom until 1837, it is problematic to establish a birth date unequivocally.

1780 George Thomas Ditmar (sic), son of George and Ann, was baptised 5 November 1780 at St Marylebone Church London (parish register, via
1784 Henry John Dettmer, son of George and Ann, was baptised at St Marylebone Church, 23 August 1784 (parish register, via

William David Dettmer was apprenticed to Samuel Bury in the Tallow Chandler's Company, City of London.

The transcript of the original 1787 apprenticeship entry in the Records of London Livery Companies (ROLLCO) database records his surname as Dettmar and gives his father's forename as Christopher. At first sight this might seem to raise doubts as to whether this was the same person. However, the author has identified primary source evidence to confirm this was indeed the William David Dettmer in question, this being a City of London Freedom Admissions record made many years later in 1844 when William David finally claimed his Freedom of the City by servitude by virtue of his apprenticeship to Samuel Bury (See 1844 for a full transcription and citation reference for this record).

[Authors note: For more information on Samuel Bury, musical instrument maker, including evidence of his early connections with George Goulding (later of Goulding and D'Almaine) in 1788 see Debenham 2014, Joseph Merlin in London, 1760–1803: the Man behind the Mask. New Documentary Sources in The Royal Musical Association Research Chronicle, Vol. 45, Issue 1, 130-163.]

1795 Samuel Dittmar (sic), son of George and Ann, was baptised 7 January 1795 at St Pancras Old Church.

William Dettmer married Mary Ann Betts (b. ca 1771) on 6 February 1797 at St Anne's Church, Soho.

1798 William Gotleib Dettmer, son of William and Mary, was baptised 14 January 1798 at St. Pancras Old Church.

George Dettmer first appears in Land Tax records at 7, Gresse Street in 1799, co-incidentally the premises which had been occupied from 1773 - 1782 by Louis Lavigne Verel, then foreman to Joseph Merlin, and from 1782- 1790 by first Thomas and then John Prusserot, a carver and gilder (Land Tax records, via

[Author's note: For more information on Verel and his relationship with Merlin and on Prusserot, see Debenham 2014, Joseph Merlin in London, 1760–1803: the Man behind the Mask. New Documentary Sources.]


George Dettmer, son of William and Mary, was baptised 11 July 1802 at St Pancras Old Church.

An advertisement placed in a Northamptonshire newspaper for an auction sale in this year included a Dettmer pianoforte with additional notes (The Northampton Mercury, 20 February 1802). So, one must ask, was the house of Dettmer already making instruments using aspects of the design of William Southwell's groundbreaking 1794 patent in contravention of his patent rights, before the Southwell v. Broadwood court case of 1803?

George Dettmer is listed in the Land Tax records in Gresse street in this year.


Elizabeth Dettmer, daughter of William and Mary, was baptised 11 October 1803 at St. Pancras Old Church.


Caroline Dettmer, daughter of William and Mary, was baptised 28 July 1805 at St Pancras Old Church.

1806 Robert Dettmer, son of William and Mary, was baptised 20 July 1806 at St Pancras Old Church.

There is a record of a marriage of a George Dettmer to Elizabeth Reeves at St Pancras Old Church on 9 November 1808.

[Author's note: Probably this was the first marriage of George Thomas, b.1780, since the parish register declares him to be a batchelor. One of the witnesses to the marriage signed himself 'George Bullocke'; it seems likely he was the George Bullock listed in the 1811 London and Country Directory as a pianoforte maker at 5, Totttenham-place.

Two later marriage records for George T. in 1822 and 1834 show that in both cases that he declared himself a widower; however a comparison of the signatures in the three parish registers reveals some disimilarities between the 1808 signature and the latter two so, though it is likely that all three marriages were for the same person, for the moment one cannot be certain.]

William Dettmer took on an apprentice named William Farlow on 10 March 1808. (Board of Stamps: Apprenticeship Books, Series IR 1; The National Archives of the UK, Kew, Surrey, England, via


William Dettmer's wife, Mary, died aged 38. She was buried 18 March 1809 in Westminster.

A few short months later, W. [William] Dettmer announced his removal from his manufactory at 7, Gresse-street to 50 Upper Mary-le-bone-street in a London newspaper.

W. DETTMER respectfully informs his Friends/ that he has REMOVED from his Piano-forte Manu/factory, No 7, Gresse-street, Rathbone-place, to more exten/sive premises, No. 50, Upper Mary-le-bone-street, Fitzroy-square/where he hopes the continuance of their favours. (The Morning Post, 26 July 1809).

On 29 November 1809 William Dettmer remarried at St Mary-le-bone Church. His new wife was named Phillis Harper, a widow.

[Authors note: A Dettmer family history website reports that William re-married, his new bride being Phillis Betts (Mrs Harper). Since William's first wife, Mary Ann, was also a Betts by birth, if this is indeed the case it seems likely the two were related, though this remains to be established.]

1810 William Dettmer is listed in the Land Tax records in Upper Mary-le-bone-street.

In this year George Dettmar (sic), cabinet maker, is listed in The London and Country Directory at 13, Gresse-street. William Southwell (occupation not given) is listed in the same directory at 11, Gresse-street, providing reliable evidence that they were close neigbours. Both also appear in the Land Tax records for Gresse-street in this year.

William Dettmar (sic) pianoforte maker, 50 Upper Mary-le-bone-street is separately listed in The London and Country Directory in this year.

1813 William Dettmer was named as an executor in George Astor's will (The National Archives, Kew: Prob 11/1550).

Camille Pleyel wrote a letter to his parents from London on 3 April 1815 which includes references to George Dettmer, thus suggesting he was still active at this time, though whether independently or with his son is not clear.

I have seen George Dettmer; our wood is still here and I shall not send it until a new order comes...

... As for the oval pianos, Dettmer is practically the only one who makes them. His instruments are good, but he has no reputation. Broadwoods are the best known, then Clementi, Stodart, Wilkinson, Tomkinson (sic), etc. etc. (Rita Benton, 1966. London Music in 1815, as seen by Camille Pleyel, Music and Letters v 47 no.1, 36)

And on 23 May 1815 Pleyel wrote again:

This morning Mr. G. Dettmer came to deliver the bill of lading for the mahogany wood and and a note for the various expenses for customs, transport of the wood, commision and brokerage the whole amounting to £4. 12s. 4d. sterling, which I paid him, in addition to the cost of the receipt. I presume you will be receiving the wood without delay and I urge you to dispose of it as soon as you can, if you can realise any profit from it. The purchase price was £55 and several shillings, to which must be added the £4.12s. which I paid today, plus the freight and the cost of the transport from Le Havre to Paris... (Benton, 1966, 40)


Edward Dettmer, son of William and Phillis, was baptised 17 July 1816

1817 Charlotte Augusta Dettmer, daughter of William and Phillis, was baptised 30 November 1817
1819 In this year George Dettmer is still listed in the Land Tax records in Gresse-street, next door but one to William Southwell.

An advertisement for square and circular pianofortes by 'G.W.Dettmer' of No. 50 Upper Mary-le-bone-street appeared in The Morning Chronicle in November of this year.

PIANOFORTES - G.W. DETTMER re/spectfully informs the Nobility, Gentry, merchants, Cap-/tains and others, that he now has on sale an elegant assort-/ment of SQUARE and CIRCULAR CORNERED PIANO/FORTES, with and without drawers, six Octave, &c. which/ he will warrant of the best materials and workmanship, at his/established Manufactory, No. 50, Upper Mary-le-bone-street, Fitzroy-square. - N.B. A liberal Allowance for prompt pay/ment. (The Morning Chronicle, 17 November 1820.)

[Authors note: It is interesting that this advertisement bears the initials 'G.W.' rather than just 'W', though the address given is the one to which William alone had moved in 1809. One may surmise that George had re-joined his son, since he no longer appears in the Land Tax records in Gresse-street after 1819. Note also that the advertisement offers circular cornered pianofortes of the type reported by Pleyel in his letter to his parents in 1815.]

A Sun Fire Insurance record for this year shows John Henry Dettner (sic) of 1 Upper Rathbone Place, turner, possibly the Henry, son of George and Ann, who was baptised in 1784.

1822 George Dettmer, widower, (b.1780) married Susan Payne at St. Mary Magdelene, Old Fish-street (Pallots Marriage Index).
1823 Caroline Dettmer (b.1805), daughter of William and Mary, married John Ashton Green in September of this year in Westminster. [Author's note: By 1839, John Ashton Green had died and Caroline, now in Australia, re-married Christopher W. May in Sydney, NSW - see 1839].

John Dettmer, musical instrument maker, was reported bankrupt in The London Gazette.

Dettmer, John, formerly of Regents-Park, afterwards of Thornhaugh-Mews, aftewards of No. 11. William-street/Hamptead Road and later of No. 11, Field Terace, Battle-Bridge, all in Middlesex, Musical-instrument Maker (The London Gazette 18080, 16 November 1824, 1900).

It appears that John Dettmer (probably Henry John, brother of William) later emigrated to Australia. See 1848, for evidence of his activities there.


William Dettmer advertised that he had terminated his engagment with Messrs Goulding and Co., whom he had been supplying for the past 20 years.


WM. DETTMER, PIANO-FORTE MAKER/ having terminated his engagment with Messrs./GOULDINGS and Co. (nearly the whole of whose PIANOS he/has supplied during the last Twenty Years), feels himself at/liberty to offer to the Professors, Amateurs and Dealers/Instruments of the best quality and materials, on unusually/low terms. The well-known character of Messrs. Gouldings and Co.'s Pianos render it unecessary for him to say more in recommendation of his manufacture, than to assure those who may favour him with their orders, that he shall continue/the same exertions which he used for the last Twenty-five/years with so much success. W.D's extensive Stock of/well seasoned materials and large premises, enables him to/keep a good assortment of PIANO-FORTES always ready for/inspection. A very liberal allowance for cash, and all/Pianos purchased of W.D. if not approved of within three/months will be exchanged, free of expence, excepting the/Carriage./ N.B. Old Pianos taken in exchange. /Address No. 50, Upper Mary-le-bone Street, Fitzroy Square, London. (Trewman's Exeter Flying Post 20 January 1825).

[Author's note: This advertisement is interesting in a number of ways. Firstly it indicates that William Dettmer had been making pianofortes for sale under the Gouldings label since at least 1805. Secondly, her research has shown that Gouldings had a connection with Samuel Bury (to whom William Dettmer was apprenticed in 1787), as far back as 1788 when George Goulding advertised his music selling agency based at Bury's premises. For further information on this connection see Debenham, 2014 Joseph Merlin: the Man behind the Mask, 21.]


On 30 August 1827 William Dettmer was granted a patent for 'certain improvements on pianofortes'

... The object of the patentee in adapting this invention to pianofortes, is to enable the instrument, after having been properly tuned, to be brought into unison with other instruments of a different pitch, by raising or lowering the tone of all its strings by a simple operation, instead of the trouble of tuning each string separately' (Journal of the Franklin Institute, 1831 Vol. VIII, p 256)

1831 In a letter to The London Journal of Arts and Sciences the contributor, identified only by the initials F.L.S, offered his observations on the practical application of William Dettmer's 1827 patent. From this the reader learns that instruments using this innovation were at that time being made by Mr. Tomkisson, pianoforte-maker of Dean-street. [Author’s note: Newly identified information, sourced by Debenham, 24 January 2016]
1833 George Dettmer, aged 93 of Praed-street, Paddington, London, died; he was buried 28 April 1833 at St James, Westminster
1839 Caroline Green, second daugher of William and Mary Dettmer, remarried in Sydney, Australia to Christopher Watkin May in June 1839. (The Sydney Herald, 19 June 1839)
1843 George Thomas Dettmer (b. 1780) died, leaving his possessions to his second, possibly third wife, formerly Mary Ann Wales, and his two daughters, Rosina Amelia and Eloise Elizabeth (Will: The National Archives, Kew, Prob. 11/1980).

Very belatedly William David Dettmer claimed his Freedom of The City of London by virtue of his servitude to Samuel Bury in the Tallow Chandler's Company (see also 1787 above). The original handwritten record of this event reads:

The first Court held on Tuesday the/19th day of November 1844 and in/the Eighth year of the Reign of/Victoria of the United Kingdom of/Great Britain and Ireland, Queen.

This day upon reading the humble Petition/of William David Dettmer, it appearing that the/Petitioner was bound as an Apprentice according to the Custom of this City to Samuel Bury Citizen and/Tallow Chandler of London by Indentures dated the/2nd day of January 1787 and duly served him the/full term of seven years according to the Covenents/therein contained whereby he had a right to the Freedom of this City in the said company of/Tallow Chandlers but for particular reasons prayed to be admitted thereto by virtue of his service/ and in the Company of Turners, it is ordered/that the said William Daniel [sic] Dettmer be admitted/into the Freedom of this City by virtue of his/Service and in the Company of Turners./Merewether (City of London Freedom Admissions Papers, held in The Metropolitan Archives; retrieved via

1845 William Dettmer was declared bankrupt in London (The London Gazette 20435, 24 January 1845)
1846 The firm, now trading under the name of Geo. Dettmer and Son 'late of Upper Mary-le-bone Street', announced the opening of a new retail store at 27, Edwards-street, Portman Square, offering for sale instruments by Broadwood and Collard and Collard (Daily News, 20 December 1846)

The firm of George Dettmer and Son, pianoforte makers, was listed in The London Post Office Directory at 20 1/2 Clipstone Street, as well as at Edwards Street.

It appears that at some point following his 1824 backruptcy, John Dettmer (probable brother of William), had emigrated to Australia, as is evidence by an advertisement placed in a Sydney newspaper in that year.

NOTICE - JOHN DETTMER, Pianoforte/Tuner and Repairer, from the firm of/George Dettmer and Son, London, begs to/state that he will tune and repair at very mo-/derate charges, combined with punctuality and/prompt attention. 56 Pitt-street South (The Sydney Morning Herald, 21 November 1848)


William Dettmer emigrated from London to Sydney, Australia where his second daughter, Caroline, was already living with second husband, Christopher Watkins May. Surviving descendants in Australia report that he arrived on board the ship the Julindur, accompanied by two of his granddaughters, Elizabeth Ann and Adelaide Rose Jackson (children of his late daughter Elizabeth and her husband Dr John Jackson) who had been left orphaned in London. [Authors note: my thanks to Bill Piper for providing the correct spelling of the ships name, 22 January 2016]

Evidence from a contemporary Australian newspaper shows that William set up in business there at 51, Hunter-street.


GEORGE DETTMER AND SON,/Patent Grand Cabinet and Square/Pianoforte Manufacturers (established fifty/years in London), beg most respectfully to/inform the gentry and public of Sydney and/its environs, that having had many years/practical experience enables them to tune and/repair in a superior manner. G. Dettmer and Son, having sent a considerble number of in/struments to the colony, solicit the patronage/of tuning and repairing them./ N.B. - Hammers recovered with the new/patent hammer cloth, which gives a more/ sweet and pleasant tone, and is far more/durable./ 51, HUNTER-STREET./ Orders received at Mr. Aldin's Tobacconists, George-street. (The Sydney Morning Herald, 5 May 1849).


William is to be found trading under several variations of the family name quite inconsistently in a number of Australian newspaper advertisements over the next several years; these include 'George Dettmer and Son'; 'G. Dettmer and Son'; 'George W. Dettmer' and 'Wm. Dettmer' (various contemporary Australian newspaper advertisements).

One advertisement placed in this year states that he had been in the trade for 'upwards of 50 years', providing further corroborative evidence that his partnership with his father, George, had begun during the first decade of the century (The Maitland Mercury & Hunter River General Advertiser, 12 November 1851)


William Dettmer died at the home of his son-in-law Christopher W. May at Tempe, near Windsor, Australia on 20 February 1858, aged 85.

DETTMER - February 20, at Tempe, near Windsor, at the residence of his son-in-law, Mr. C.W.May, after a lingering illness, Mr. William Dettmer, many years a pianoforte manu-/facturer, Marylebone-street, London and for the last nine years in this colony, aged 85 years. (The Sydney Morning Herald, 10 March 1858)

DEATH OF MR. DETTMER - This gentleman, well known in Maitland and Newcastle as a pianoforte tuner, departed this life on the 20th [illegible word] at Tempe, near Windsor, at the residence of his son-in-law, Mr. C.W. May. Mr Dettmer had reached the advanced age of eighty-five. He was an excellent tradesman and was, moreover, distinguished for his good humour and other estimable moral qualities. Mr Dettmer, when young, stood on Blackfriar's Bridge, London and saw the first batch of convicts pass over on their way to found this colony. Many people in Maitland and elsewhere will regret the untimely demise of this cheerful and agreeable old gentleman. (The Bathurst Free Press, 13 March 1858)

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