Miscellanies.. 403 
10. The price of the subscription for each parcel is $8,88, (22 
florins, ou 48 franes Argent de France.*) ‘Two months after send- 
ing each parcel, we shall’ expect to receive this sum from the sub- 
scribers. The subscription will remain open to the end of the year. 
Those amateurs who may not yet be able to appreciate the plan 
and execution of our enterprise, will see the opinion of Prof. Leon- 
hard, expressed upon the publication of our first proposals. (Zetts- 
chrift fiir Mineralogie, Fevrier 1828, pp. 162.) 
“‘T expect much,” says he, “ from this enterprise of the Mineral- 
ogical Institute. It will furnish the means of understanding in future 
with more precision and facility, the objects and their names: it will 
put an end to vague determinations and doubtful arrangements ; a 
thing of no small importance in respect to petrifactions. From the 
considerable number of subscribers, in all countries, of which a list 
has been shown me, it is presumed that these collections will be gen- 
erally received. Hence, in a few years they will doubtless be met 
with in all public cabinets, and in many private collections. It will 
therefore be possible hereafter to refer to specimens in these collec- 
tions in geological works, and it will be easy from thence to make 
comparisons.” 
Heidelberg, May, 1829. 
Although the subscription for these rocks and petrifactions is not 
promised to continue open longer than to the close of the year 1829, 
yet probably it will not be too late to make application after that peri- 
od: and it is earnestly hoped that so good an opportunity for enrich- 
ing the public and private cabinets of this country, will not be lost. 
A letter put into the post office in any part of our country, with the 
postage paid as far as New York, will reach Heidelberg safely, 
and expeditiously, if the following address be put upon It: Au Comp- 
toir de Mineraux de Messieurs David and Adolph Zimmern, Heid- 
elberg, sur le Neckar, Allemagne—via New York et Havre. - It 
may be well, also, to put on the opposite side of the letter, the fol- 
lowing direction in English: Messrs. David and “Adolph Zimmern, 
at the Mineral Magazine, Heidelberg, Germany, via New York and 
Havre. 
: oning the franc at 18 1-2 cents, dividing 8,83 by 22, we get 40 cents and 
four tenths as the value of the florin, and this value I have used in all the subse- 
quent reductions of the prices of the collections: judging it more safe to trust to this 
than to any tables of exchange within my reach. 
