1895.] ^ i [Sachse. 



city, at the confluence of the Wertach and the Lech, and com- 

 mands a view of the surrounding country. This solitary tower, of 

 wliich I have here a contemporaneous engraving by Hess, dates 

 back to the tentli century, but lias been altered and restored upon 

 several occasions, notably towards the close of the sixteenth 

 century, when it was raised by the celebrated architect, E. Holl, to 

 its-present height of 326 feet. It was on this occasion that Schiss- 

 ler was commissioned to construct the four sun-dials, two of which 

 are seen in the engraving. This tower was built as a watch-tower, 

 to discover the approach of the enemy. At the present time it does 

 duty as a look-out for the fire patrol. 



The old chronicler goes on to state that Schissler received the 

 sum of 400 florins for his labor on the four dials, while his wife was 

 given 6 florins for assisting her husband. 



The account also says tliat the survey of the city was commenced 

 in 1598. Schissler also surveyed, with the aid of his son, the 

 Lechstrom, completing the work in 1603. From official records it 

 appears that for five years' labor he received the sum of 500 florins, 

 in addition to his expenses. 



The Memorial Buch further states that his MeisterstUck or c/ief- 

 (i'ceuvre was placed in the Mathematical Hall of the Zwinger, or 

 Royal Museum at Dresden. It was a qicadratum geomctricum, and 

 bears, beside his usual inscription, the date 1569. This apparatus 

 was for the purpose of measuring both elevation and distance, in 

 which the divisions were given by transverse lines. 



He also constructed an ingenious odometer or measuring wheel 

 (Wegmesscr) which is described by Kirchner, p. 221, Ed. Colon., 

 1647. 



From the above enumerations of Schissler's handicraft, we are safe 

 in assuming that the Augsburg artificer was one of the most ingeni- 

 ous mechanics of his time. 



In searching for other scientific authorities who were acquainted 

 with instruments having a similar property, and had left a record of 

 the fact, it is found that Varenius, in his Geographica Genera/is, 

 makes some general mention of what may be called a refracting 

 dial. 



Leybourne, in his work on Gnomonicks (London, 1682), notes 

 that such dials were to be made in two ways, one where the gnomon 

 was hidden all under the water ; the other, where the point was above 

 the water. Our own specimen was evidently one that combined the 



