736 GEOLOGY. 



year 1780, found the nearly perfect head of an animal, which greatly attracted public 

 curiosity, and long baffled the attempts of naturalists to ascertain its true place in the 

 animal kingdom, at a period when comparative anatomy was yet in its dawn. The dis- 

 coverer was soon afterwards compelled to abandon his prize, upon the ecclesiastics of the 

 city claiming the possession of it, on the ground that it had been taken from a domain 

 belonging to the cathedral. Its further history is curious, and has been detailed in a 

 French work specially devoted to the object. Upon the commencement of the wars of 

 the Revolution, a number of savans from Paris accompanied the French army to the 

 gates of Maestricht, for the express purpose of obtaining this animal remain. The gar- 

 rison were invited to hoist a flag on the town hall, where it was known to be kept, in 

 order that the besiegers might avoid destroying that building with their shells. Upon 

 the capture of the city, the relic was transported to Paris, where it now remains. Cuvier 

 confirmed a previous suggestion concerning it, that it belonged to a gigantic marine 

 animal, nearly allied to the monitor, the remains of which have since been discovered in 

 the upper chalk near Lewes by Dr. Man tell, and in the green sand of the United States. 

 This reptile received the name of the mososaurus, or the lizard of the Meuse, from the 

 place of its first discovery. It is supposed to have been from twenty to thirty feet in 

 length, the oar-like construction of the tail indicating a capacity to move rapidly in the 

 ocean after the large and powerful fishes, upon which, from the great size of the jaws and 

 teeth, it is conceived to have preyed. The era when this creature first appeared in the 

 seas of the ancient earth was immediately subsequent to the age when the ichthyosaurus 

 governed the inhabitants of the deep, and it doubtless performed the same office that of 

 checking an excessive multiplication of the occupants of the ocean during the period of 

 its reign, which appears to have been exclusively confined to the cretaceous epoch. 



The physiognomy of chalk districts is not unprepossessing in general, and it is often 

 very attractive, presenting a series of bold hills, with valleys intersecting them in every 

 direction, remarkable for their smooth and flowing outline, affording a scant though 

 sufficient herbage for numerous flocks of sheep. The economic value of the deposits is 

 of high importance, the flints supplying a material used in the manufacture of glass and 

 porcelain, and the chalk itself being eminently serviceable in agriculture. A soil, to be 

 fertile, must contain a certain proportion of argillaceous, siliceous, and calcareous earth, 

 and where the latter is deficient, the land may be improved by the addition of a few 

 loads of chalk, more than by any quantity of animal or vegetable manure used alone. 

 Still, Cuvier and Brongniart represent sterility as one of the most prominent features of a 

 chalk deposit, and refer to Champagne as an instance of its soil being almost uninhabit- 

 able. Mr. Conybeare also remarks, that in this country the population of the chalk dis- 

 trict is less than that of any other secondary rock, in proportion to its size, and large por- 

 tions of it are unenclosed commons, only used as sheep-walks. This arises from the 

 mineral being in excess, and from the dryness of the strata. Many of the valleys of 

 Kent and Sussex are, however, extremely fertile, and upon a chalk soil, well manured, 

 some of the cereal grasses flourish luxuriantly. The beech also thrives well, and now, 

 when a member of parliament vacates his seat by accepting office under the crown, the 

 stewardship of the Chiltern Hundreds, he takes in hand a task no longer required that 

 ! of watching over a chalk domain in Oxfordshire, once famous for the harbour afforded to 

 banditti by its woods and thickets of beech. 



