also commended books by Lockhart in discussing a problem on roots proposed by John Pell to Silius Titus. Lockhart and Young then influenced the subsequent work of Rehuel Lobatto. Lockhart's books were mostly self-published: A Method of Approximating Towards the Roots of Cubic Equations Belonging to the Irreducible Case (1813) Nieuwe en algemeene leerwijze om biquadraten op te lossen waarbij de systemas van Descartes en Euler tot biquadraten met derzelver tweede termen worden voortgezet (1823) Nieuwe oplossing van cubiek-vergelykingen door juiste uitdrukkingen, en ook bij nadering, zonder beproeving of gissing (1825) Extension of the celebrated theorem of C. Sturm, whereby the roots of numeral equations may be separated from each other, with copious examples (1839) Resolution of Two Equations (1839) Resolution of Equations by Means of Inferior and Superior Limits (1842) The Nature of the Roots of Numerical Equations (1850) Family Lockhart married twice. With his first wife, Mary Coxe, daughter of Leonard Coxe of Philadelphia, a dispossessed loyalist of the American Revolution, he had three daughters and a son. With his second wife Elizabeth, whom he married in 1805, he had six sons and two daughters; she died in 1843 at age 56. Lockhart's children included: James, the eldest son, a barrister and poet; James Augustus Lockhart, officer in the 41st Regiment, killed at age 21 on 8 September 1855 in the Crimean War was his son. John Ingram (1812–1889), a writer and friend of Nicolaas Beets. Miles, who married Anna Rebecca Charlotte, daughter of Major Robert Stewart of the 94th Regiment; James Haldane Stewart Lockhart was their son. Maria, who married John Smith of Ellingham Hall, Norfolk in 1828. Notes 1763 births 1852 deaths English bankers English mathematicians