the Academy of Sciences at Haarlem. 447 



vered by the same sea, which, at an inferior level, now washes 

 their shores. On the other hand, the illustrious Swedish ge- 

 ologist, Nilson, has shown, that another part of Scandinavia 

 remains at the same level, or rather, that it sinks; so that the 

 phenomenon observed appears to consist in a see-saw move- 

 ment, upon an axis whose position is not thoroughly known. 

 The Society requests, that by a particular examination it be 

 discovered, whether in Holland, or the neighbouring states of 

 this kingdom, a similar elevation or depression be observable ; 

 or whether it can, on the contrary, be concluded, from the na- 

 ture of their soil and the fossil remains which they contain, 

 that nothing of the kind has taken place there. 



The Society recapitulates that it has proposed, in preced- 

 ing years, the thirteen following questions, to be replied to 

 before the 1st of January, 1839. 



I. — Sulphur, considered in relation to its existence in na- 

 ture, being met with in associations and localities widely dif- 

 fering from each other, some of which have given reason to 

 suppose that this substance is produced in a different man- 

 ner from the greater number of minerals, or, indeed, that it 

 may perhaps derive its origin from organic bodies ; — the So- 

 ciety requires the natural history of sulphur, particularly with 

 reference to the different combinations and relation under 

 which it presents itself; and the deductions which may be 

 thence gathered, concerning its origin and production. 



II. — The progress of Chemistry having made known a great 

 number of methods by which, from very different materials, 

 sugar may be produced ; it is required, What are the differ- 

 ent species of such artificial sugar ? And what is the best 

 method of producing each kind ; Also, which of these kinds 

 is the most useful, and the most suitable to take the place of 

 cane-sugar, and other kinds now in use ? 



III. — What are the different species of animals which, 

 by perforating, destroy the piles and other wooden works 

 which surround our shores and dykes, in many places ? — 

 What is the natural history and anatomy of these animals ? 

 What are the means which have hitherto been employed to 

 resist their devastations ? Finally, what will further research- 

 es into their natural history and comparative anatomy offer, 

 as a means of preservation preferable to those already known? 

 The Society does not wish that, in reply to these questions, 

 anything should be repeated which is already known. It re- 

 quires, on the contrary, that new researches should supply 

 what is deficient in the old ones. 



Vol. II. — No. 20. n. s. t^ 



