that the greatest of Dutch statesmen might have become famous as a mathematician had the cares of administration permitted him to pursue the abstract studies that he loved.  Of the scientific achievements of Christian Huyghens (1629-95), the brilliant son of a brilliant father, it is difficult to speak in adequate terms.  There is scarcely any name in the annals of science that stands higher than his.  His abilities, as a pure mathematician, place him in the front rank among mathematicians of all time; and yet the services that he rendered to mathematical science were surpassed by his extraordinary capacity for the combination of theory with practice.  His powers of invention, of broad generalisation, of originality of thought were almost unbounded.  Among the mathematical problems with which he dealt successfully were the theory of numbers, the squaring of the circle and the calculation of chances.  To him we owe the conception of the law of the conservation of energy, of the motion of the centre of gravity, and of the undulatory theory of light.  He expounded the laws of the motion of the pendulum, increased the power of the telescope, invented the micrometer, discovered the rings and satellites of Saturn, constructed the first pendulum clock, and a machine, called the gunpowder machine, in principle the precursor of the steam engine.  For sheer brain power and inventive genius Christian Huyghens was a giant.  He spent the later years of his life in Paris, where he was one of the founders and original members of the Academie des Sciences.  Two other names of scientists, who gained a European reputation for original research and permanent additions to knowledge, must be mentioned; those of Antoni van Leeuwenhoek (1632-1723), and of Jan Swammerdam (1637-80).  Leeuwenhoek was a life-long observer of minute life.  The microscope (the invention of which was due to a Dutchman, Cornelius Drebbel) was the favourite instrument of his patient investigations, and he was able greatly to improve its mechanism and powers.  Among the results of his labours was the discovery of the infusoria, and the collection of a valuable mass of information concerning the circulation of the blood and the structure of the eye and brain.  Swammerdam was a naturalist who devoted himself to the study of the habits and the metamorphoses of insects, and he may be regarded as the founder of this most important branch of scientific enquiry.  His work forms the basis on which all subsequent knowledge on this subject has been built up.

To say that the school of Dutch painting attained its zenith in the period of Frederick Henry and the decades which preceded and followed it, is scarcely necessary.  It was the age of Rembrandt.  The works of that great master and of his contemporaries, most of whom were influenced and many dominated by his genius, are well known to every lover of art, and are to be seen in every collection of pictures in Europe.  One has, however, to visit the Rijks