168 Portable Equatoreals. 



be found by the fishing process, and found at once by the 

 setting- of the circles, without touching the eye-piece end of 

 the telescope. 



Perhaps it may not be uninteresting to give an account of 

 the performance of the writer's portable instrument on one 

 particular occasion, when all circumstances combined to display 

 it to the best advantage. The writer was desirous of proving 

 the capabilities of the Portable Equatoreal in the presence of 

 an astronomical authoress, well-known to the readers of the 

 Intellectual Obseever — one whose works prove her to be pecu- 

 liarly well qualified to appreciate any instrument calculated to 

 illustrate the recreative character of the science. An opportunity 

 occurring for showing the working of the instrument to several 

 persons, among whom was the Hon. Mrs. Ward, one magnificent 

 morning in July, 1859, the telescope and clip were placed in a 

 small carpet bag, and a ticket was taken, via Midland Eailway,' 

 to a delightful rural spot in Gloucestershire. The place being 

 quite new to the writer, and the latitude and longitude differing 

 from what had been adopted for the adjustment of the instru- 

 ment at Clifton, so as entirely to throw out of the field of view 

 any object sought without taking this difference into account — 

 and there being no land mark previously determined for a south 

 point, etc., made the occasion a good test of the capabilities of 

 the instrument, and one which all present appreciated. The 

 first step was to obtain a south mark. For this purpose, the 

 sun, a watch, and the hour-circle of the clip placed horizontally, 

 furnished the necessary materials. Making the requisite cal- 

 culation for longitude, and taking an azimuth from the *sun — 

 previously calculated for several intervals from noon in case of 

 need — I obtained a mark. A stick placed in the ground 

 answered the purpose. The equatoreal was placed on a table on 

 the lawn. One word by way of explanation of the azimuth, 

 for the beginner. The time being known, the distance in 

 degrees from the south, of a point in the horizon which is cut 

 by a plumb-line held so as to bisect the sun, becomes known, 

 and thus the south point is obtained by calculation. It is to be 

 remembered that all this is for placing the instrument in a state 

 of adjust mi iit so that the axis may point to the pole as pre- 

 viously stated. 



On the occasion referred to, tho problem given was to find 

 Venus in broad daylight, by means of the graduated little 

 circles before mentioned. I now look at my watch, and having 

 previously calculated how many degrees from her meridian 

 passage VenUS will bo by the time that I have completed my 

 ad jus! mi nt , I set tho telescope to the proper declination and 

 distance from south corresponding to such interval from her me- 

 ridian passage, and predict that at such and such a minute she 



