20 Modern Microscopy. 



perhaps inappreciable to the novice, yet as he advances all 

 these minor details come up as very real ghosts, haunting 

 him in his work and causing him to avoid that which would 

 have been useful to him. If the foot of the microscope be 

 shod with cork, so much the better, as vibration is thereby 

 partly insulated,, and the annoyance caused by scratching 

 tables is avoided. It must be clearly understood, however, 

 that even if this form of foot be not made in proper propor- 

 tion its advantages will be annulled. 



Next to this foot in point of convenience and rigidity we 

 would place the Jackson model, as shown to the instrument 

 on page 29. This, if properly made, is but little inferior to 

 the tripod, but it is heavier. 



There are many others made, mostly modifications of the 

 Jackson model, and then* rigidity can be tested by placing 

 the instrument in a horizontal position, racking the body 

 out, and then observing whether there is any tendency to 

 topple over. If so, have nothing to do with it. The double- 

 pillar form, with flat tripod foot, as shown on page 34, is a 

 very good and convenient one. It is adopted by several 

 firms for largest size instruments, and is certainly hand- 

 some. 



Last on our list of feet we should place the horseshoe 

 pattern, as shown on page 17. The great advantage this 

 possesses over all others is its compactness for portability. 

 It originated on the Continent, and is preferred both there 

 and in English medical schools, etc., before any other. 

 It is usual in laboratories to work with the microscope 

 in a vertical position, and while the instrument is so 

 placed the horseshoe foot is quite firm. If it be placed 

 horizontally, however, as the amateur usually employs it, 

 even with a well-made foot there is a tendency to side- 

 falling. It would be well, therefore, not to select this form 

 of foot when choosing a microscope. The order of prefer- 

 ence for the foot of the microscope would be : 



1. The tripod foot, as shown to instruments page 81 and 

 frontispiece. 



