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THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



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he Basilicata in Naples, to the south of Rome. Indeed, most of th e 

 rases are got over a wide district, far beyond the confines of Etruria 

 Proper. 



The sixth group is from the Neapolitan province of Puglia or Apulia. 

 These are much like the vases of Nola, with pale backgrounds and figures 

 of the reddish maroon. 



The terracottas are of various origin and require classification, so that 

 the locality may be known. They are chiefly Etruscan. In the centre of 

 this group are various divinities and mythological groups. 



Besides the vases included in the Etruscan lioom, are others in various 

 parls of the Museum. There is a large collection of vases and terracottas 

 from Athens in the Hronze Room. In the Townley collection are Roman 

 vases, urns, and terracottas. In the Egyptian Rooms are vases and similar 

 works, of various times and styles. 



Altogether, the collection of vases and terracottas in the Museum is 

 copious, but to make it complete it is very necessary that there should be 

 a series of Chinese porcelains. The Museum of Economic (jeology con- 

 tains some specimens of ancient and modern earthenware, but the British 

 Museum must be looked to as the chief school for artists. 



(To be continued.J 



DESCRIPTION OF A UNIVERSAL TIME TABLE. 



By F. Bashforth, Esq. 



The calculation of Railway Time Tables is attended with considerable 

 difficulty and liability to error, owing to the various velocities of different 

 classes of trains and the variation of gradients and stations stopped at. 

 The importance of the correctness of these tables, coupled with the diffi- 

 culty of obtaining that result, have led me to contrive a little instrument 

 ■which, when the stoppages and the time of starling and arrival are deter- 

 mined, will give the times of arrival at each station exactly as they appear 

 in the bill, regard being had to varying gradients, and consequently vary- 

 ing velocities. There could be no doubt of the perfect success of a mere 

 geometrical contrivance, but to remove any doubt that might he felt, and to 

 explain my notions to my friends, I have constructed a universal time 

 table for the main line of the Manchester and Leeds Railway, which is 

 about 01 miles long, and has 21 stations. The result is perfectly satisfac- 

 tory. I employ two scales; the vertical is of 40 minutes— the horizontal 

 of 8 miles to the inch, but they might have been respectively 60 and 20. 

 The instrument is arranged on a board 11 inches square. 



Let A B, fig. 1, represent 30 miles, andfthe perpendicular C B, CO 

 minutes, and suppose a train to be travelling along A B with a uniform 

 Telocity of 30 miles per hour. The time of describing A 6 will be found 

 by applying the vertical scale to measure the perpendicular c\b ; for 



Time in A 4 A. b be. 



TimeTn~AB — AB ~ BC 



But B C represents time in A B, and therefore b c represents time in 

 A * ; and so on for any other distance. 



Suppose, however, that when the train comes to D, the velocity falls 

 from 30 to 20 miles per hour. Draw E F parallel to A B, and cut oft' 

 E F = 20 miles. Erect the perpendicular F G, and make it 00 minutes 

 by the vertical scale. Join E G. Then the time of arrival^at any point 

 d, will be found by applying the vertical scale to the perpendicular c d, 

 and readicg off the minutes; and so on if there bejjmore changes of velo- 

 city. 



The above is applicable to a train travelling with varying velocities, bu 



without stoppages. If we suppose the train to lose 5 minutes by stop ping 

 at a station at b, then this time will never be recovered, and every point in 

 'he time line to the right of b c, must be raised 5 minutes. If there be 

 another loss of 4 minutes at d, every point in the time line to the right of 

 d e, must be raised through 4 minutes additional ; and so on for other 

 stoppages. 



Fig .6. 



Suppose that on a railway there are stations A, b, C, d, e, F, g, A, I 

 where A and I, are the termini, and C, F, first class. A to b, is 3 miles; 

 to C, 2 , ; C to (i, 5i ; d to e, 4 ; e to F, 3 ; F to g-, 2 ; ^ to A, 3 ; and 

 h to I, miles. The first eight miles can be travelled at the rate of 25 

 miles per hour, the next ten at 20 miles, and the remaining distance at 30 

 miles per hour. Fig. 3, shows a series of strips of boxwood of equal 

 length and thickness, but whose breadths represent the distances betwixt 

 the stations, measured by the horizontal scale. The section at fig. 0, show 

 the provision made at each division, by a pin and two holes, to ul low f^ 

 stoppages, as at C and F, fig. 4. The time lines, .t y, z «■, are laid down 

 as in fig. 1. The former is for trains passing from A to I, the latter from 

 I to A. 



Fig. 4. 



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