890 PROCEEDINGS OF SECTION J. 



the boundaries of the block, the traverse lines of the standard 

 survey adjacent, and sketches of the main stations to be con- 

 nected to with reference to bearings, &:c., is forwarded with 

 the instructions for measurement to the detail surveyor. 

 When speaking of the standard survey I mentioned that the 

 surrounds should enclose from three to six sheets or blocks, 

 the reason of that is that it is generally advisable to employ 

 one detail surveyor on all the blocks within a complete surround 

 of the standard work, in order that his work may be closed 

 harmoniously on it. 



The best plan is for the detail surveyor to go over the block 

 first, sketch in every detail, and choose the positions for his 

 stations before he commences his instrumental or chainage 

 work. He then starts from one of the main stations and 

 traverses through the whole of the blocks he has on hand, 

 fixing the position of every detail by actual bearing and 

 distance, ordinary off-setting not being permissible. The 

 principal judgment required is in choosing his interior 

 stations in order that the work may be carried out with no 

 greater number of stations than is necessary ; along the streets 

 his traverses should form base lines with the same relation 

 to the building lines or alignment as those of the main 

 standard survey. The method of angling for the traverse 

 lines in the detail survey is similar to that recommended for 

 the standard survey, except that generally but two repeats 

 are necessary instead of four or more. The bearings of 

 radiations to the details are read direct from the instrument 

 by the ordinary back angle method, repeats being unnecessary, 

 as the bearing of the starting hue is always rechecked. The 

 lengths of the sides of all buildings are also measured, so that 

 the three sides of every triangle being taken any error in the 

 length or bearing of a radiation is discovered when the plan 

 is plotted. The chainage of the traverse lines is conducted 

 in a similar manner to that described for the standard survey, 

 but with not quite so much care, and therefore with greater 

 rapidity. 



This class of survey is so different to the ordinary routine 

 of country work in any of the colonies that, when initiating 

 it, it is advisable to start with, at any rate, one or two ex- 

 perienced men to train the junior surveyors, and the experience 

 so gained will soon enable them to decide upon the best 

 method of carrying out the work with the minimum expendi- 

 ture of labour. 



The field notes should be all kept in ink in the field, and 



