136 VOCABULARY OF 



VOCABULARY 



OP 



SCIENTIFIC TERMS. 



Absorption, a sucking up ; a term in Chemistry, used when a gas loses 

 its properties by combination ; thus, if muriatic acid gas be intro- 

 duced into water, it is absorbed, and muriatic acid is formed. 



Accelerated Motion, or Acceleration, is that which receives fresh acces- 

 sions of velocity : this particularly refers to the falling of heavy 

 bodies towards the centre of the earth through Gravitation. 



Achromatic, a term applied to Telescopes contrived to remedy aber- 

 rations and colours. These were first invented by Mr. John 

 Dolland. 



Acidimetry, the measuring of the power or strength of acids. 



Acids, are those substances which produce a sour taste, probably 

 caused by the shape of their particles. Acids are known by their 

 changing vegetable blue colours, as syrup of violets, into red. 

 They unite with earths, alkalies, &c., and form numerous salts. 



Acoustics, the doctrine of hearing and sound. See page 49. 



Adhesion, a species of union that takes place between the surfaces of 

 bodies : this must not be confounded with Cohesion. Adhesion 

 implies an union to a certain point between two substances either 

 of similar or dissimilar kinds ; Cohesion that which retains the 

 component particles of the same mass. 



JEdipile, a hollow tube of metal with a long pipe, formerly used to 

 show the elasticity and force of water converted into steam. If this 

 instrument be filled with water, and exposed to a pretty strong heat, 

 the water will issue from the pipe, in the form of vapour, with pro- 

 digious violence. The well-known Jack of Hilton is an Jiolipile ; 

 as also Fluster, a celebrated German idol : the latter being filled with 

 water, and set over a fire, would apparently become covered with 

 perspiration, which was considered as a miracle by the ignorant. 



Aerolit/is, certain stones which occasionally fall from the atmosphere. 

 See page 56. 



Aerology, the science of the air as to its properties. 



