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Miscellaneous Intelligence. 



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III. Miscellaneous Intelligence. 



1. Great Exhibition in London. — The scientific portion of ihe great 

 exhibition though falling fiir short of the reasonable expectations of 

 men of science, presents yet many objects of interest and I have thought 

 that a few notes taken upon the spot might prove useful if only as hints 

 to those wishing to purchase apparatus abroad. Of a liberal display 

 of balances for chemical and physical purposes, we have to notice the 

 instruments of Messrs. Deleuil and Collot in Paris, of A. Oertling in 

 Berlin, L. Oertling in London, and the United Slates balances of Mr* 

 Saxlon, Deleuil* exhibits balances of three sizes; the largest or bal- 

 ance for physical researches is intended to bear as much as iwo kilo- 

 grammes in each scale and with this load will turn vvith one milli- 

 gramme ; it is mounted upon a cast iron base and placed within a large 

 case with glass doors, so that bulky objects, ^s glass globes, &c., may 

 be conveniently weighed. When the benm rests upon its supports, the 

 pans are also supported separately ; in throwing the beam off its sup- 

 port the pans are suspended, their knife edges resiing upon agate planes ; 

 the index is placed in the centre of the beam and descends to a scale 

 below. The workmanship of the whole instrument is admirable; its 

 price with weights is 1500 francs. The large balances of MM. Collot 

 freres, are very similar to those of DeleuiU differing chiefly in having 

 a g5ass base instead of one of cast iron. DeleuiPs smaller balas^ces 

 for chemical purposes when loaded with 200 or 300 grm., are sensible 

 to half a milligramme ; the beam as in the other instrument is of brass ; 

 the pans are of platinum suspended by silver wires; they are not sus- 

 pended from knife edges, but by means of steel hooka resting in stir-t 

 Tups upon the end of the beam, an arrano^ement which is certainly ob- 

 jectionable. The beam in these balances is divided for a sliding weight 

 but there is no sliding rod as in Oertling's instruments. The assay bal- 

 ances by the same maker deserve the highest praise ^ot workmanship 

 and elegance of consiruction, they are of steel with an index pointing 

 vertically upward; the whole is admirably arranged and of exfjuisiie 

 finish. A. Oertling of Berlin exhibits also boih chemical and physical 

 balances ; the former are too well known and too generally appreciaied 

 in this country to require special notice; 



weigh from one kilogramme to one-half milligramme; their construc- 

 tion is upon the whole similar to that of the chemical balances, the 

 beam being divided and furnished with a sliding rod and weight. There 

 are however two indices or pointers instead of one placed horizontally, 

 one at ench end of the beam and each is furnished with an index scale. 

 This arrangement is perhaps advantageous for very large balances 

 Avhere a slight deflection of the beam might occur, but it appears un- 

 necessary and is certainly inconvenient in smaller instruments like 

 those employed in delicate physical investigations. The division upon 

 the beam and the use of a sliding weight appears also unadvisable in 

 balances of this size with which it is rarely necessary to weigh very 

 rapidly, but the principal and serious objection to the construction of 

 Oertling's larger balance lies in the suspension of the pans, which rest 



♦ Deleuil, 8 Rue du pont de Lodi..* ► 



the larger mslrumenis will 



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