382 SEC. 12. APPLIED MECHANICS. 



Drawing No. 1 represents the apparatus arranged for experiments of 

 extension. 



Drawing No. 2 represents the apparatus arranged for experiments of flexion. 



Drawing No. 3 represents the apparatus arranged for experiments of the 

 compression of long bars. 



The deformations in the bars occasioned by this apparatus are measured 

 with a cathetometer constructed by Mr. Brauer, and the primitive section of 

 the bar with an apparatus by the same engineer. The correctness of all 

 these registerings is given in ^-^ of the millimeter. 



II. SPECIAL COLLECTIONS. 



COLLECTION OF THE ORIGINAL MODELS OF STEAM ENGINES AND 

 OTHER MACHINES OF JAMES WATT. PRESENTED TO THE 

 SOUTH KENSINGTON MUSEUM BY GILBERT HAMILTON^ ESQ. 



1928a. Imperfect Model of method of converting recipro- 

 cating into rotative motion by means of teeth or pins fixed to the 

 connecting rod, which take hold of teeth in a wheel, and cause 

 it to revolve. Some point of the connecting rod being guided by 

 a pin, moving in a groove, so as to keep the teeth or pins always 

 engaged in the teeth of the wheel. 



This method of converting reciprocating into rotative motion is included 

 in Specification of Patent granted to James Watt, dated October 25th, 1781. 



1928b. Two Fragments of a Model, consisting of wood 

 rods with oval holes geared internally, and apparently belonging 

 to one of the models selected frcftn the Soho Works by the late 

 Sir Francis Smith, as an illustration of one of the methods of 

 converting reciprocating circular motion. 



1928c. Model of Grinding Mill, 6 pairs of stones in two 

 sets of 3 pairs each, each set driven by a spur wheel with bevil 

 gearing. The two fly wheels are connected and driven by pin and 

 connecting rod. 



1928d. Model of Grinding Mill, with six pairs of stones, 

 in two sets of three pairs each. Each set driven from one spur 

 wheel by bevelled gearing. 



The two fly wheels are connected, and driven by one connecting rod, fitted 

 with two sets of stepped sun and planet wheels. 



1928e. Model of Boiling and Slitting Mill, driven by 

 two connecting rods, on one beam, and fitted with sun and planet 

 stepped gearing. 



