No. 4 



With Full Vertical Circle and Aluminui 



Guard. 



No. 4 



No. 4b. 



Mountain, Mining and Reconnoissance Transit. 



As made by C. L. Berger & Sons. 



NOTE. Not infrequently we are asked to make the telescope of this instrument to show objects erect. 

 This cannot be done to satisfaction, since it is impossible to make so small an erecting telescope that will have 

 the necessary power for good work and be at the same time of good quality. It seems that in all such cases 

 the interest of our friends will be best guarded if they will order Transit No. 2 or 6 , a coming nearest to 

 the desired end. Having thus acquainted our friends with this fact, we would add that we are prepared to 

 carry out their wishes in this respect, if they are willing to take the consequences upon themselves. As will 

 be noticed in the description of our Mining Transit, given later on, we are prepared to attach our interchange- 

 able auxiliary telescope, Style I, to transit No. 4, when the latter is provided with a full vertical circle. This 

 can be done safely since all the important parts are as stiff and unyielding as in our larger instruments. We 

 can also attach our solar equatorial adapter (see page 168), when style I Interchangeable Auxiliary Telescope 

 has been ordered, by the aid of which the auxiliary telescope is made to answer the purpose of a solar tele- 

 scope, thus enabling to determine meridian lines at any hour of the day. This must be considered a great 

 improvement, since no additional solar attachment will be necessary. This auxiliary telescope has a higher 

 power and adds but one pound additional in weight. 



When desired the above Transit may be provided with a 4%" horizontal circle in place of the regular 4" 

 circle without extra charge. The weight of the No. 4 with 4%" circle is about 6% Ibs., and its box is 2 Ibs. 

 heavier than the smaller box. 



However, our regular No. 4 Transit with a 4" horizontal circle is strongly recommended as being 

 superior to the 4%" circle for mountain and mining use where weight and compactness are of great 

 importance. Since it is symmetrical in design and all its parts have been tested these many years of 

 actual use in the field, with clean cut and accurate graduation* which can be readily estimated to jo" or 

 2O 11 , this small instrument enables to do most accurate work, being inferior to our large instruments only 

 in power. Greater angles of elevation and depression may also be read with the regular 4" horizontal 

 circle, which is an additional advantage, since we are frequently asked to raise the standards of the 4%" 

 transit for this purpose, bringing this latter circle close to size and weight of our transit No. b without 

 being as steady and as well proportioned as either the regular No. 4. or No. 0. 



See last testimonial on brown paper (in front of catalogue) by Mr. L. E. Van Etten. 



