20 Frith Street is a building in the Soho district of Westminster. It is located on the east side of Frith Street, close to the junction with Old Compton Street. The building which currently occupies the site of 20 Frith Street was built in 1858 by William Cooze to replace a house which dated from c1725, which itself may have replaced an even earlier building.

When the house was built in around 1725 there were fewer houses in the street (which for a period was named Thrift Street), because the north end was taken up by Monmouth House. At the time, the grounds of Monmouth House (now demolished) extended from the south side of Soho Square to Queen Street (now Bateman Street); and so during some of the eighteenth century the house's address was 15 Thrift Street. The most famous inhabitant at this address was Wolfgang Amadeus Mozart, who lived there aged eight from September 1764 during his grand tour of Europe with his father and his sister.

The site gained its current address of No. 20 Frith Street some time after 1773 when Monmouth House was pulled down, and more houses began to be built on its former grounds at the north end of the street. The eighteenth-century building at No. 20 was demolished and rebuilt in 1858, and since 1930 it has served as the stage door entrance for the Prince Edward Theatre situated on Old Compton Street. A blue plaque commemorates Mozart's stay.

History 1725 The house which formerly occupied the present site of No. 20 was built in about 1725–6, when it was occupied by Lewis Aubert, a wine merchant.

Description The 18th-century house was described in the 1966 Survey of London: Quite apart from its association with Mozart, it is of interest as one of the best early eighteenth-century fronts known to have existed in the street. Built of brick, it was four storeys high and three windows wide, although the fourth storey may have been a later addition. The windows had segmental gauged arches and the jambs were probably dressed with red brick, while within the openings were slightly recessed boxframes. There was no bandcourse between the second and third storeys, but above the latter was a moulded brick cornice returned at either end. A shop front had been inserted in the ground storey in the early or mid nineteenth century.

The 1725 building was pulled down in 1858 and rebuilt with a similar brick façade, shown in a photograph from The Musical Standard, 3 Oct. 1908.Picture of 20 Frith Street c1908

Mozart The eight-year-old Wolfgang Amadeus Mozart stayed here with his father Leopold Mozart and his sister Nannerl in 1764–65, during a well-publicised European musical tour. The Mozarts were lodgers of Thomas Williamson, a maker of corsets or stays. During Mozart's stay, the address of the building was 15 Thrift Street. More houses were built after 1773 at the north end of the street (whose name reverted to Frith Street), resulting in the current address of 20 Frith Street. See below, §Numbering changes in Frith Street.

The Mozart family had removed from No. 180 Ebury Street, probably directly to No. 15 Thrift Street, on 25 September 1764. The young Mozart gave daily afternoon public recitals, and published his Opus 3 (Violin Sonatas, K. 10–15) from that address.Facsimile title page of 1st edition: see His father had the music engraved, and sold the music at the lodgings. Mozart dedicated the set to Queen Charlotte, whose music teacher was Johann Christian Bach. Bach befriended the young Mozart, whose sonatas shows Bach's influence. It seems likely that he was a visitor to the house. It is possible that Mozart also wrote the Symphony No. 4 in D major, K. 19, here,The Viennese composer and writer Eduard Lannoy owned an 18th-century set of parts for this early work. as well as the concert aria for tenor "Va, dal furor portata", K. 21/19c, and the short motet for chorus, God is our Refuge, K. 20. The London Sketchbook, K. 15, also dates from this period. The Mozart family was still in Frith Street on 30 May, leaving London in July.

Jean Baptiste Troye

The miniaturist Jean-Baptiste Troye exhibited dioramas (scale models of landscapes) at No. 20 in the early 1800s. His exhibitions consisted of "the most beautiful models and reliefs of countries, cities, mountains, &c. celebrated either for natural beauty or historical occurrences associated with them."

Troye was the pupil or (assistant) of the geologist and chemist Charles-François Exchaquet, who made the first accurate relief models (in wood) of the Mont Blanc chain, a part of Valais and the St. Gotthard group. A model of Mont Blanc which is (or was) in the possession of the Swiss Alpine Club may partly be Troye's work.

Exchacquet's models, like Troye's, were realistically painted with glaciers made of spath (i.e. spar) and the models were about 1.40m x 40 cm (about 4' 6" by 1' 6"). One of Exchaquet's models still existed in 1920, having been presented to the museum of Görlitz by Baron de Gersdorf. (Baron von Gersdorff from Saxony, possibly?). Gersdorf authenticated the first ascent of Mont Blanc by Jacques Balmat and physician Michel-Gabriel Paccard in 1786. Exchaquet was also the director of mines and foundries at Servoz in Haut-Faucigny, where attempts were made to emulate the success of the English steel-makers who, however, were using the very best imported Swedish Oregrounds iron.

In 1816 Troye co-authored with one S. Glover A Description of the Inundation of the Valley of Bagnes in Swisserland.In 1818 a huge landslide occurred in the Vals de Bagnes in the Swiss Alps, travelling several miles into the upper Rhone valley. Picture of Lac de Mauvoisin, 1818 – the lake dammed by an ice fall of the Gietroz Glacier which caused the disaster. The event was described by Hans Conrad Escher: "... in half an hour the lake was completely emptied, and the five hundred and thirty millions of cubic feet of water which it contained, thundering down into the valley with a rapidity and violence of which no idea can be formed ... Enormous heaps of pebbles and rocks, which the floods had carried off higher up, were deposited in the plains ... runs through the town of Martigny ... covers the whole plain with thick mud ... According to the unanimous testimony-of the inhabitants, the flood took up half an hour in passing every point which it reached; thus, in the short space of thirty minutes, the whole mass of the water of the lake, drawing with it all the debris, and forming a column of more than 530 millions of cubic feet, passed every part of the valley. Source: , cited in: Montgomery, Keith. "Neuchatel, Switzerland 1819" The development of the glacial theory 1800–1870: Episodes 1800 – 1840 University of Wisconsin – Marathon County. Retrieved: 5 January 2013Troye was not the only inhabitant of No. 20 with an interest in floods. Joseph Menchen had a business in New York selling electrical scenic stage shows for amusement parks such as Luna Park in Coney Island and the 1904 St Louis World's Fair. One of these was a diorama representing the Johnstown Flood, with moving water and fire effects. See The Billboard, 2 November 1907 and The Billboard, 2 March 1907 Troye published an account of Mont Blanc and his models in 1819. There is a picture of either Troye's or Exchaquet's highly detailed work in .

There is a fine plaster medallion of William Thomas Brande, attributed to J. B. Troye c1820, in the National Portrait Gallery.William Thomas Brande at the National Portrait Gallery, London.

Jean Baptiste Troye's son was the artist Edward Troye, America's foremost 19th-century horse painter, whose influences were George Stubbs and John Sartorius.Troye, Edward at The Web Gallery of Art, retrieved 2012-12-14 Born in Lausanne in 1808, he studied art in England for a number of years before moving to the United States.

1820 A bookseller, Thomas King junior, lived at No. 20 from 1820 to 1822 Maxted, Ian (2003). The London book trades 1775–1800: a preliminary checklist of members. Names F. Exeter Working Papers in British Book Trade History.

John Green, aged 16, was found guilty in October 1820, of stealing 15 lbs. of lead, value 8s., the goods of Thomas Matthews Redaway, and fixed to a certain dwelling-house of his. No. 20, Frith-street, Soho. He was transported for seven years. A certain felon named John Green was transported to Australia on board the MorleyPainting of the Morley arrived at Sydney Cove, 10 April 1817. and arrived in Newcastle, New South Wales on the Elizabeth Henrietta on 14 March 1821.John Green search results at Free Settler or Felon?

1827–1839 Frederick Rothenburg, late of No, 20, Frith-Street appeared on 13 July 1827 at the Court for Relief of Insolvent Debtors, Portugal Street, Lincoln's Inn Fields, as did Augustus Armand, formerly of No. 20, Frith-Street, assistant to a Jeweller, on 13 November.London Gazette, No. 18378, 13 July 1827 p. 1531 (Issue p. 1505)London Gazette, No. 18414 13 November 1827 pp. 2341 and 23422 (Issue p. 2329)Picture of the court in Portugal Street before its demolition In 1828 John Pike and James Clark upholders and furniture warehousemen were insured by the Sun Fire Office (now RSA Insurance Group) as was William Landon, gent., in 1830. A fire started "at 9½ p.m." on 18 September 1839 next door at No. 19, a bookbinder's. The back workshops were burned out and three adjoining buildings were damaged.

William Cooze

William Whitley Cooze (c1794 – 1866), a house decorator, plumber and glazier had his business at No. 20. A business partnership with William H. Penley was dissolved in 1841.The London Gazette, No. 20081, 15 March 1842 p. 732 In 1844 he was selling "Improved Marble papers" (i.e. wallpaper), and calling himself 'Marine Decorator to her Majesty'.The Indian Mail, 4 October 1844 p. 574 The first royal yacht to be powered by steam, HMY Victoria and Albert, was launched the previous year.

In 1847 John Penny, aged 30, was indicted for stealing 12 feet of lead-pipe, value 10s.; the property of "William Witley Coorze", his master for four years; and Richard Garrett, aged 27, for feloniously receiving the same, knowing it to have been stolen. Penny was sentenced to three months after a plea for leniency, and Garrett received a year in prison. John Green (see above) got seven years in Australia for a similar crime in 1820. In 1851 Cooze was employing 15 men in his house-decorating business. The original house at 20 Frith Street (dating from around 1725) was demolished and rebuilt in 1858. Cooze was declared bankrupt on 16 April 1866The Edinburgh Gazette, 24 April 1866, p. 507 and died shortly afterward.

Soho Club for Working Girls

The Soho Club for Working Girls met at the rear of 20 Frith Street between 1880 and 1884. The club was established by the Hon. Maude Stanley in order to improve the lives of young women workers in London and provincial towns. The Soho Club began in a very humble way in three small rooms at No. 5 Porter Street, Newport Market. There were forty-four members, and an average attendance of fourteen every evening. The premises, after a few months, proved too small, and a workshop at the back of 20 Frith Street was secured, at a rental of £50 a year. This building served until 1884, when Miss Stanley purchased, aided by her many benevolent friends, the "commodious and beautiful building" at 59 Greek Street at a cost, for the freehold, building and furnishing, of £7,200. The club eventually grew into London Youth (Federation of London Youth Clubs).

1885–1911 Wells & Co., wholesale tea dealers, had their offices at No. 20 in 1895. NB Almost all the other wholesale tea dealers listed in this P.O. Directory had offices in the City of London in the EC (East Central) postal district. Wells & Co. were almost unique in the list in having premises in Soho, W. London, quite some distance from the financial and business district.