viii A GERMAN SCIENCE READER. 



names. Occasionally the meaning of a compound or derived 

 word used in a scientific sense may be slightly at variance with 

 the significance suggested by the elemental parts, and, as in all 

 languages, the same word may have in different connections 

 different meanings ; in such cases we must rely upon the context 

 for the exact shading. 



2. PARTICIPIAL CONSTRUCTION. 



The readiness with which .the participles in German express 

 properties, attributes and descriptions causes them to be employed 

 in scientific German more frequently than usual, where they take 

 the place of relative clauses. No general rule can be given for 

 their translation, except that the present participle would indicate 

 existing attributes and qualities, while the past participle would 

 express completed actions or past conditions. And the so-called 

 future passive participle with zu, an act to be done, or a condi- 

 tion to be accomplished. The following examples will afford 

 illustrations of these principles: page 27, das in der Atmo- 

 sphare enthaltene Wasser, the water which is contained in 

 the atmosphere; das zum Eis gewordene Wasser, the 

 water which became ice ; page 45, Senkrecht auffallende 

 Schallwellen, sound-waves which fall perpendicularly ; page 

 60, zu Pulver zerfallener Soda, pulverized soda; page 60, 

 das am meisten zu empfehlende Schweismittel, the 

 welding-flux most worthy of recommendation; page 68, seine 

 durch die beiden Blatter fest bezeichneten Endpunkte, 

 its termini plainly shown by the two leaves ; page 88, eine nicht 

 zur Erschb'pfung fuhrende Arbeit, a work which does not 



