In 1745 the composer Christoph Willibald Gluck (1714–1787) came to London seeking fame and fortune. At this period in time London and its environs were twice the population of Paris, and three times the population of Vienna, meaning that it offered more market opportunities (as opposed to patronage) than anywhere else, and acted as a magnet for musicians throughout Europe.1
Gluck's opera La caduta de' giganti was only repeated five times after the first performance.2 In March he composed another opera: Artamene (actually adapted from previous operas he had written) which wasn't performed at all; and in that same month he gave a concert with Handel—the reigning musical king in London, who had said that Gluck 'knows no more counterpoint than my cook'.
In April, Gluck played a concerto on 26 glasses at a benefit for himself.3 An advertisement appeared in the General Advertiser for 23 April 1746:
At Mr. Hickford's Great Room in Brewer's-street, on Monday, April 14, Signor Gluck, Composer of the Operas, will exhibit a Concert of Musick. He will play a Concert upon Twenty-six Drinking Glasses, tuned with Spring water, accompanied with the whole Band, being a new Instrument of his own invention, upon which he performs whatever may be done on a Violin or Harpsichord; and therefore hopes to satisfy the Curious, as well as the Lovers of Musick. To begin at Half an hour after Six. Tickets Half a guinea each.4
Horace Walpole mentions this concert in a letter:
The operas flourish more than in any latter years; the composer is Gluck, a German; he is to have a benefit, at which he its to play a set of drinking glasses, which he modulates with water. I think I have heard you speak of having seen some such thing.
Gluck left London in ???. We know he performed on his 'Drinking Glasses' again in Copenhagen in 1749, but that's it. Gluck's fortunes improved considerably after his London venture—perhaps he didn't need to resort to his 'Drinking Glasses' any more.
From Harsdörfer we know that the 'wet-finger' concept was known in Germany, Gluck's native country, so perhaps Gluck got the idea for the musical glasses from Harsdörfer, or from his travels in Italy, and brought that idea to London.