Bred and raced by Major Henry McCalmont, he was admired for his gameness and stoutness despite his inherent laziness. It was said that he often left his jockey rather more tired than he at the end of a race. A Triple Crown winner, his only defeat came from Raeburn (b.c. 1890), although an ongoing rivalry with Ravensbury (b.c. 1890) had made his jockey work.

He was described as a "beautifully made horse of size and substance" with a "splendid shoulder, strong back, lengthy muscular quarters and capital bone" although it was said that his forelegs were inferior to those of his sire.

He went to stud at Cheveley Park, near Newmarket, where he was twice second on the list of Champion Sires although he did not get the best mare books. Isinglass died in December of 1911.

Race Record
At 2: Won a Maiden Plate (Newmarket), New Stakes, Middle Park Plate, beating Ravensbury.
At 3: Won Two Thousand Guineas Stakes, beating Ravensbury and Raeburn, Newmarket Stakes, Derby Stakes, beating Ravensbury and Raeburn, St. Leger Stakes, beating Ravensbury, 2nd Lancashire Plate, won by Raeburn.
At 4: Won Princess of Wales's Stakes, Eclipse Stakes, beating Ladas, Jockey Club Stakes, Ascot Gold Cup.

Notable Progeny
Bridge of Sighs (b.f. 1905), dam of Light Brigade (br.c. 1910), Great Yorkshire Stakes, and sire in America of Preakness winner Dr. Freeland (ch.c. 1926), Kentucky Oaks winner Rose of Sharon (br.f. 1926), and Ariadne (br.f. 1926), dam of Discovery (ch.c. 1931).

Cherry Lass (b.f. 1902), One Thousand Guineas Stakes, Oaks Stakes.

Confection (b.f. 1909), dam of Pendennis (b.c. 1917), Poule d'Essai des Poulains, and 4th dam of Fine Top (br.c. 1949).

Cornfield (b.f. 1904), dam of Love in Idleness (bbr.f. 1918), Oaks Stakes.

Coronation (b.f. 1908), ancestress of numbers of winners in France and Italy, including Match (b.c. 1958), Relko (b.c. 1960) and Torbido (br.c. 1941).

Glasalt (b.f. 1898), dam of One Thousand Guineas winner Canyon (b.f. 1913), the latter dam of Colorado (br.c. 1923). Glasalt was also dam of King William (b.c. 1908), Dewhurst Stakes, and 4th dam of American Triple Crown winner Citation (b.c. 1945 Bull Lea).

Glass Doll (b.f. 1904), Oaks Stakes.

Goody Two Shoes (b.f. 1899), dam of Charles O' Malley (bbr.c. 1907 Desmond) Ascot Gold Vase, and ancestress of Nureyev (b.c. 1977) and Sadler's Wells (b.c. 1981).

Jacobite (ch.c. 1898), Prix Royal Oak.

John o' Gaunt (b.c. 1901), sire of Burne Jones (br.c. 1915), Premio Parioli, Kennymore (b.c. 1911), Two Thousand Guineas, and Swynford (br.c. 1907), St. Leger and Champion Sire in 1923.

Lady Lightfoot (b.f. 1900), dam of Prince Palatine (b.c. 1908), St. Leger, sire of He Goes (br.c. 1917), Irish Derby.

Louviers (b.c. 1906), Newmarket Stakes, sire of Landgraf (b.c. 1914), Deutsches Derby, hte latter the sire of Ferro (br.c. 1923), Deutsches Derby and Hausfreund (b.c. 1919), Deutsches Derby.

Louvois (b.c. 1910), Two Thousand Guineas, sire of St. Louis (b.c. 1919), Two Thousand Guineas, and Harpsichord (bbr.f. 1918), she the dam of Royal Minstrel (gr.c. 1925) and ancestress of Gallant Man (b.c. 1954 Migoli).

Lygie (ch.f. 1900), dam of Medeah (ch.f. 1906), Prix de Diane and Prix Royal Oak. Lygie is also ancestress of the Triple Crown winner Omaha (ch.c. 1932) and the Kentucky Derby winners Decidedly (gr.c. 1959) and Johnstown (b.c. 1936).

Malatesta (ch.f. 1898), dam of La Farina (ch.c. 1911), Prix Lupin, sire of Dorina (ch.f. 1923), Prix de Diane, La Dame de Trefle (ch.f. 1922), Poule d'Essai des Pouliches, Tapin (b.c. 1921), Poule d'Essai des Poulains, and Bubbles (ch.c. 1925), Prix Lupin.

Mrs. Despard (b.f. 1905), dam of McKinley (bbr.c. 1916), Poule d'Essai des Poulains, and Zori-de-Zi (b.c. 1910), Derby Roman.

Star Shoot (ch.c. 1898), National Stakes, Leading Sire in America from 1911 to 1917 and again in 1919, sire of Grey Lag (ch.c. 1918), Belmont Stakes, Sir Barton (ch.c. 1916), Triple Crown, Wing Ting (b.f. 1904), Kentucky Oaks, and Wistful (ch.f. 1914), Coaching Club American Oaks.