Many other, often autograph, Rembrandt drawings, including some in the British Museum, were retouched by later hands, no doubt with the intention of increasing their value by giving them a greater degree of finish.  Nor were the Museum and its benefactors protected from the other traps set in the art market. For example, not one of the four Rembrandt drawings thought to derive from the foundation collection formed by Sir Hans Sloane and acquired for the nation in 1753 is now considered to be by the master himself. Most had been consigned to the boxes and folios of Rembrandt’s school before the end of the 19th century. Sloane’s Angel appearing to the Shepherds ( Cat. no. 101) is listed in the first complete inventory of Sloane’s drawings, compiled in 1845, as a ‘very effective’ work by Rembrandt. No doubt its rich chiaroscuro conformed to preconceived notions of Rembrandt’s style and directed attention away from the pedestrian quality of its pen work. Thirteen years later the drawing was seen by E.J.T. Thoré-Bürger, the connoisseur now best remembered for re-establishing the artistic personality of Jan Vermeer of Delft. Bürger’s study of the Museum’s drawings, published in the Revue germanique of 1858, provides a fascinating insight into the standards applied to the appreciation of Rembrandt’s drawings at that time. He echoed the opinion expressed in the Sloane inventory, describing the Annunciation to the Shepherds as a ‘dessin capital’ and adding that it must have been a study for Rembrandt’s etching of 1634 of the same subject. In fact its composition has little in common with the print and the drawing is probably the work of a pupil, made around 10 years later.
The drawing’s reputation did not endure. In 1877, the Dutch art historian Carel Vosmaer published the final edition of his monograph on Rembrandt, which included lists of the artist’s works in European collections. He described the Angel appearing to the Shepherds as ‘douteuse’.  This adjective was repeated by Eugène Dutuit in 1885  and, apart from its listing by A.M. Hind as an anonymous work in his 1915 catalogue of the British Museum’s drawings by Rembrandt and his school, the sketch never again featured in the literature on the artist until the British Museum’s exhibition catalogue of 1992. Crucially, it was omitted from the exhibition of the Museum’s holdings of Rembrandt’s work in 1899 on the authority of the then Keeper, Sidney Colvin; Colvin’s exhibition catalogue formed the basis of Hind’s publication, in which just once sentence is devoted to the drawing: ‘Has something of the appearance of being a copy from an original drawing by the master’.
Hans Sloane was not primarily a connoisseur and his drawings formed only a small subsection of his collection of manuscripts. In accordance with his encyclopedic, antiquarian interests, most of his drawings were arranged by subject matter rather than by artist. Aesthetic qualities were not a priority and in this respect he differed from the two men who were to make the other major bequests of drawings to the Museum in the 18th century, William Fawkener (d. 1769) and the Rev. Clayton Mordaunt Cracherode (1730–99). Both appear to have been true amateurs of art in the old-fashioned sense and their collections of Rembrandt drawings have fared considerably better than Sloane’s. Two of the four bequeathed by Fawkener, and nine of Cracherode’s sixteen drawings are still regarded as authentic in the present catalogue.  On the other hand, a study of the Cracherode inventory has revealed that two of his drawings, believed at least since 1747, when they appeared in the sale of Jonathan Richardson, Sr, to be copies by Rembrandt after Indian miniatures, and registered in 1845 as ‘query if by Rembrandt’, are in fact Indian work of the early 18th century.  Rarely can such an erroneous attribution have survived for so long. The drawings were eventually transferred to the Department of Asia in the 20th century (see under Cat. No. 56, note 10.)
One collection of Rembrandt drawings that has been reduced by the reappraisal of subsequent scholarship to a surprising degree is that of Richard Payne Knight (1721–1824). Keenly involved in the aesthetic debates of his time and a promoter of the Picturesque in landscape as in art, he was undoubtedly a well-informed connoisseur. His taste was unusual in that he valued the Dutch school as highly as the Italian and he was also wealthy enough to buy at least some of his drawings at top prices.  His bequest to the Museum in 1824 was one of the largest and most generous it has ever received, and through it the Department of Prints and Drawings acquired no less than 1,169 drawings.
Knight’s collection contained several especially fine drawings by Rembrandt, who was probably the artist he most prized, including the Lamentation at the Foot of the Cross (Cat. no. 9), the Black Drummer and Commander on Horseback ( Cat. no. 17, described as ‘very fine’ in the Register), the Lioness devouring a Bird ( Cat. no. 29) and the Coach (Cat. no. 55). Yet of the 63 Rembrandt drawings that he left the Museum, less than one third remain under Rembrandt’s name today. Among those that have been reattributed, several were considered in the 18th and 19th centuries not only to be by the master himself, but also to be prime examples of his work. The Young Man seated on a Window-Sill (now tentatively attributed to Abraham van Dijck, cat. no. 1) was described in 1821 by C. Josi as, very naturally expressed: one perceives an idle young man in the whole attitude of the figure. The head and the arm which form the main part are distinguished by strong touches and a grand luminosity: all the rest is only cursorily indicated. The original is broadly washed and in the manner of a painting, in brown and black. It is one of those good drawings which are only seen very rarely today. The price would be around 20 Louis. 
Josi’s remarks are of interest in suggesting that collectors were in pursuit of particular types of drawings, especially those that were highly finished and pictorial. This accords with the taste for the most sought-after Rembrandt etching of the 18th century, the 100 Guilder Print. The Young Man seated on a Window-Sill was also accepted as capital by Thoré-Bürger, by Vosmaer, who described it as a délicieux dessin and as a portrait of Rembrandt’s son, Titus, and by Eugène Dutuit.  It was however omitted from the 1899 exhibition by Sidney Colvin and this again proved fatal. Other than in Hind’s catalogue, it was mentioned in the literature just once, in a footnote, until 1992. 
Payne Knight presumably laid out a considerable sum to acquire such a sheet. In the case of another of his Rembrandts, the Christ with Mary and Martha ( Cat. no. 112 ) it has emerged that he paid 350 livres at the de La Mure sale in Paris of 1791, a high price in the plentiful art market of the French Revolutionary period. The drawing’s qualities are self-evident, and it was again particularly mentioned by Josi, as another of the pictorial studies that he most admired. Thoré-Bürger described it as ‘superbe’  and on 28 August 1874, it impressed Vincent van Gogh, who described the drawing at length, if somewhat inaccurately, in a letter he wrote three years later to his brother Theo (letter 100, 18 September 1877):
from the rich treasure of his [i.e., Rembrandt’s] heart he produced, among other things, that drawing in sepia, charcoal, ink, etc., which is in the British Museum, representing the house in Bethany. In that room twilight has fallen; the figure of our Lord, noble and impressive, stands out serious and dark against the window, which the evening light is filtering through. At Jesus’ feet sits Mary who has chosen the good part, which shall not be taken away from her; Martha is in the room busy with something or other – if I remember correctly, she is stirring the fire, or something like that. 
The drawing was rejected by Sidney Colvin in 1899 (who advanced the name of Samuel van Hoogstraten) but more tentatively described as ‘doubtful’ by Hind in 1915. He felt ‘on the whole inclined to accept it as the master’s work’, but since then it has also more or less vanished from the Rembrandt literature. Yet it remains one of the most remarkable drawings to have emerged from the master’s studio.
Payne Knight probably acquired the Abraham and the Angels, now generally given to Rembrandt’s pupil, Nicolaes Maes (see Maes, cat. no. 2), less expensively. He may have bought it as by Rembrandt at the Greffier Francois Fagel sale of 1799, when it fetched 13 shillings.  The price was not excessive for a drawing by Rembrandt, especially for one that was precisely of the finished variety that appealed most to 18th-century connoisseurs. Twenty-six years before, in 1773, it had been sold at the Lempereur sale in Paris to the Prince de Conti for the exceptional sum of 639.19 livres. It fetched half that price (320 livres) – still a substantial figure – at the Prince’s own sale in 1777, in the catalogue of which it was described as a dessin capital.  If any doubts about its authenticity had been responsible for depressing its price, they were not taken seriously at the British Museum, where it was exhibited from 1858–60 as by Rembrandt. Thoré-Bürger thought it of première qualité and it was also accepted by Vosmaer and Dutuit,  but once again its omission by Colvin from the 1899 exhibition dampened further interest. In 1905, W.R. Valentiner persisted with the Rembrandt attribution and identified the central figure in the right-hand group as Hendrickje Stoffels. But in 1924 he confirmed the attribution to Nicolaes Maes that had been tentatively proposed by Hind and it remains under Maes’s name today.