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PERIODICAL PHENOMENA OF ANIMALS AND VEGETABLES. 323 
‘at each step, whether the atmospheric influences are in a normal state, or 
whether they manifest any anomalies. 
The desire of devoting myself to the study of periodic phenomena upon a 
rather extensive scale, led me to request several men of science both at home 
and abroad to aid me with their views and observations*. The favourable 
reception given to my requests has allowed me to believe that I was not de- 
ceived as to the importance of the proposed researches; I likewise saw that 
it would be possible to compare our climate with those of the neighbouring 
countries, by direct and simultaneous observations, and to obtain, for Belgium 
in particular, valuable data which at present we do not possess. 
However, to proceed in a useful manner, it is necessary above all things 
that the observations should be made on the same plan, and it was not with- 
out reason that the men of science to whom I applied, requested instructions 
as to the objects to be observed, and the course to be taken in the observa- 
tions so as to render them comparable, an essential condition for the attain- 
ment of the proposed object. The following instructions have been drawn up 
to meet this demand, from suggestions furnished by MM. Cantraine, De Selys- 
Longchamps, Dumortier, Kickx, Martens, Mowen, Spring, Wesmael, &c, » 
There is one important remark to make, that should not be lost sight of, 
viz. that we should agree upon certain observations which should be made in 
preference, and essentially bear on the same scientific points in the several 
countries in which the observations are made, The field to be explored is 
so immense, that unless some rallying-points are adopted, the different ob- 
servers will run a great risk of not concurring, and thus almost losing their 
labour. For instance, when we point out some. plants or animals which it 
will be more especially desirable to observe, we do not wish to underrate the 
_ utility of observations made on other species; but this will be in order to 
obtain points of comparison, or standards around which other observations will 
_ easily arrange themselves. Our appeal may probably receive attention only 
from isolated observers, and it is impossible for them to comply with all the 
_ demands which we make respecting periodical phenomena; but if they are 
' desirous of undertaking those labours of detail to which we shall confine our 
_ instructions, they will at least learn what should be their starting-points so as 
_ to keep within the limits of the system generally adopted. 
f 
if 
* The observations on flowering were commenced in 1839, in the garden of the Royal Ob- 
' Servatory at Brussels. The results obtained in 1839 and 1840 were printed at the end of the 
" observations on the meteorology, magnetism, and temperatures of the earth in 1840, in vol. 
iy. and xv. of the ‘ Mémoires de l’Académie Royale.’ In 1841, the simultaneous observa- 
tions of MM. Kickx, Cantraine, Fr. Donkelaer, Martens, Morren, V. Deville, De Selys-Long- 
‘champs, Robyns, Dr. Gastone, Van Beneden, Galeotti, Spring, Schwann, &c. commenced, 
‘This system of observation was further extended in 1842 and 1843, and has been carried 
pend the frontiers of Belgium. The new observers are MM. de Spoelberg and Debroe 
at Louvain, Fredericq and Spae at Ghent, M*Leod at Ostend, Vincent at Brussels, De 
“Martius at Munich, De Caisne at Paris, the Baron d’Hombres Firmas, jun. at Alais, B. Vala 
at Marseilles, Brayais at Lyons, Couch in Cornwall, Blackwall in Wales, De Pierre and Wart- 
" mann at Lausanne, M. Achille Costa at Naples, Scherer, Camille Rondani and Colla at Parma, 
_ Van Hall at Groningen and the Horticultural Society of Utrecht, who desired to form the 
central point for the collection of observations made in the kingdom of the Netherlands, 
which the learned Counsellor von Martius has been so obliging as to do for Bavaria and Ger- 
“many in general. The new assistance which has been promised in different parts of the globe, 
_ give reason to hope that we shall soon be able to deduce the most valuable results from so ex- 
_ tensive an association. Among the learned bodies which have promised us their support, we 
_ May mention especially the Association of Natural History of Switzerland, the Royal Botanical 
~ Society of Ratisbon, the National Institute of Washington, the Philosophical Society of Phila- 
 delphia ; but we ought especially to congratulate ourselves that one of the most illustrious coun- 
_trymen of Linnzus, M. Berzelius, has spoken favourably of our scientific crusade in the Aca- 
 demy of Stockholm, where its formation was originally proposed, about a century ago. - 
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