Mary seems to have first made Wallace's acquaintance when Wallace, who was an excellent teacher, taught mathematics at the Royal Military College at Great Marlow in Buckinghamshire. When teaching there, he began a mathematical journal which contained mathematical problems and puzzles. Mary submitted solutions to some of these and started a mathematical correspondence with him.

When Mary told Wallace that she wished to make a deep study of mathematics and astronomy he recommended her a small library of books. Mary bought them in 1813 when she was 33 and used and valued them till the end of her long life.

All were recent publications and many were in French. Here is a list:

Biot | Analytic geometry and astronomy |

Callet | Logarithms |

Clairaut | Figure of the earth |

Euler | Algebra |

Euler | Isoperimetrical problems (in Latin) |

Francoeur | Pure Mathematics |

Francoeur | Elements of mechanics |

Lacroix | Algebra |

Lacroix | Differential and integral calculus |

Lacroix | Finite differences and series |

Lagrange | Theory of analytic functions |

Laplace | Mécanique céleste |

Laplace | Analytical theory of probabilities |

Monge | Application of analysis to geometry |

Poisson | Treatise on mechanics |

**Note by:** *Helen Cook*