ON SCIENCE IN SCHOOL CERTIFICATE EXAMINATIONS. 487 



3. Some conspicuous stars and constellations. A circular chart to be drawn 

 ehowing the Plough, Cassiopeia, Vega, and Capella, with the Pole Star 

 occupying (nearly) the centre. This, pinned to rotate on a cardboard base, 

 serves to record roughly the positions of the stars at different hours of the 

 night and early morning. 



Discussion of the records indicates a uniform diurnal rotation of the starry 

 sky about an axis drawn (nearly) to the Pole Star. Specially enterprising 

 pupils determine the approximate inclination of the axis to the horizon. 



4. Does the sun appear to move around the same point in the sky as the 

 stars? An affirmative answer obtained by observing the uniform rotation of 

 the shadow of a thin rod. directed towards the stellar pole, upon a cardboard 

 disc fixed at right anglee to its length. Use of this (or equivalent) apparatus 

 as a sun-dial. 



At the earth's poles the rod (or ' style ' of the sun-dial) would be vertical ; 

 on the equator it would be horizontal. Parallels of latitude are lines of 

 identical inclination of the style. Elucidation by means of a globe. 



5. The following may be commence-'i in preparation for discussion in 

 Second Year : 



(«) Record of the noonday (or ' meridian ') altitude of the sun measured 

 in degrees by a simple instrument ; 



{b) Record (by means of the rotating star-chart in § 3) of the position of the 

 circumpolar stars at the same hour (e.g., 9 P.M.) on different datee. 



B. General Physics. 



Under this title are grouped simple exercises preparatory to the formal 

 study of hydrostatics mechanics, and the 'properties of matter.' Much of the 

 work should be taken in close association with the course in mathematics. 



1. Density and specific gravity. Determination of weights by the balance 

 and of volume by calculation or displacement. 



2. The mechanism of the balance and the conditions for true weighing. 

 The laws of the lever. The grocer's scales. Weighing-machines. 



The pressure on the fulcrum of a loaded lever. The centre of gravity of 

 a body as a fulcrum, and as the ' centre ' of the weights of its parts. 

 Experiments, toys, &c., illustrating stable and unstable equilibrium. 



Simple calculations and laboratory experiments on centre of gravity, &c. 



3. "Time-measurement. (To be taken in connection with A. 4.) Essentials 

 of the mechanism of a simple clock driven by a weight or a spring and 

 controlled by a pendulum. (A single-handed clock, like that of Westminster 

 Abbey, is most suitable.) 



Isochronism of the pendulum. Effects of loading or changing length 

 of pendulum. The ' simple ' pendulum ; connection between swing-period and 

 length. Experimental determination of simple pendulum equivalent to a 

 given pendulum. The balance-wheel in watches and clocks. 



Ancient time-measures : the water-clock, the hourglass, &c. 



4. Examination of common pieces of mechanism, such as a door-lock, the 

 ' three-speed ' gear of a bicycle. (There is scope here for individual work, 

 involving written descriptions aided by diagrams, &c.) 



5. The mariner's compass ,• simple investigation of properties of magnets 

 to elucidate its use. Measurement of deviation of magnet from the south- 

 north line established in A. 1. 



C. Beat. 

 1. The varying warmth and coldness of weather as dependent on the 

 season, direction of wind, &c. The thermometer : how it works : expansion 

 of mercury. Necessity of a standard scale of graduation (compare w-eights and 

 measures). Experimental graduation of a thermometer by placing it in hot 

 and cold water together with a thermometer already graduated. 



smooth curve is drawn through the recording points A well-drawn specimen 

 is pasted on a wooden or cardboard cylinder to be used in the discussion and 

 to serve as a permanent record. The method of ' cylindrical projection ' thus 

 taught may usefully be applied in subsequent geography lessons. 



