CLOUDS AND RAIN. 385 



quantity of the heads which lie before them, and catching 

 one at the extremity, they apply them immediately to the 

 anvil and hanmier, and by a motion or two of the foot, the 

 top and the head are fixed together in much less time than 

 it can be described, and with a dexterity only to be acquired 

 by practice ; the spectator being in continual apprehension 

 for the safety of their fingers' ends. The pin is now finished 

 as to its form, but still it is merely brass ; it is therefore 

 thrown into a copper containing a solution of tin and the 

 lees of wine. Here it remains for some time, and when 

 taken out assumes a white, though dull appearance : in or- 

 der therefore to give it a polish, it is put into a tub contain- 

 ing a quantity of bran, which is set in motion by turning a 

 shaft that runs through its centre, and thus by means of fric- 

 tion it becomes perfectly bright. The pin being complete, 

 nothing remains but to separate it from the bran, which is 

 perfectly similar to the winnowing of corn, the bran flying 

 off, and leaving the pin behind it for immediate sale. 



LESSON 133. 



Clouds and Main. 



Conge'ries, a mass of small bodies heaped up together. 



A CLOUD is a collection of vapour, suspended in the at- 

 mosphere. In other words, it is a congeries of watery par- 

 ticles raised from the waters, or watery parts of the earth, 

 by the solar or electrical fire. These watery particles, in 

 their first ascent, arc too minute, and too much separated by 

 their mutual repulsion, to be perceived ; but as they mount 

 higher and higher, meeting with a greater degree of cold, 

 losing their electricity, or by some process employed by Na- 

 ture for this purpose, they are in a certain degree condensed, 

 and rendered opaque, by the re-union of their parts^o as to 

 reflect and absorb light, and become visible as clouds. 



The lowest part of the air being pressed by the weight of 

 the upper against the surface of the water, and continually 

 rubbed upon it by its motion, attracts and dissolves those 

 particles with which it is in contact, and separates them 

 from the rest of the water. And since the cause of solution 



