88 



SCIENCE-GOSSIP. 



costs in case complete £ti I2s. 6d. With one eye- 

 piece, an inch and a quarter inch objective, 

 and a special cheap but efficient Abbe con- 

 denser, the whole will cost £6 os. 6d. With 

 sliding coarse adjustment instead of the rack and 



R. &.]. Beck's "Continental." 



pinion the purchaser will save a guinea, whilst a 

 focussing and swinging sub-stage arm will cost 15 

 shillings more. With a rack and pinion focussing and 

 screw centring sub-stage, 40 shillings more. The 

 instrument is well and strongly made and capable of 

 doing good work. We illustrate the complete 

 instr\mient. 



A higher class instrument made by the same firm, 

 and which for finish and workmanship is, we think, 

 well worth the extra money, is their "Continental 

 Model," which we illustrate herewith, complete. 



The price of this stand only, in case, with horse-shoe 

 foot, as illustrated, coarse adjustment by rack and 

 pinion, micrometer screw fine adjustment, large 

 vulcanite stage, rack and pinion focussing and screw 



I\11SS \l\\ Mll'iLM SlIMKiT," 



centering sub-stage, is £t. With iwo_ eyepieces, 

 i inch and \ inch objectives, laj-i;i; iVbbe condenser 

 with iris diaphragm, fitted also with swinging arm to 

 carry coloured glasses or stops for dark ground 



illumination, the price is ;^lo iSs. A spiral focussing 

 adjustment instead of the rack and pinion centering 

 sub-stage will save 15 shillings in the total. 



Messrs. Ross, Limited, of New Bond Street, make 

 cheaper models than the one we have selected, but 

 keeping in view the requirements necessary for real 

 work, which we enunciated beforehand, we figure 

 their "New Model Medical School and Educational 

 Microscope." This instrument has coarse adjustment 

 by rack and pinion, micrometer screw fine adjust- 

 ment, horse-shoe foot, and a specially-designed rack 

 and pinion focussing (but non-centering) sub-stage, 

 which allows the condenser and the iris diaphragm to 

 be swung aside independently of each other. The 

 price of the stand, with one eyepiece only, in case, is 

 £^ 15s. With Abbe condenser, iris diaphragm, 

 f and \ inch object glasses it will cost ^9 5s. For an 

 extra 10 shillings Messrs. Ross so arrange the stand 

 that the pillar can be reversed upon the foot, and the 

 whole microscope thus turned right round. When 

 it is being used in the inclined or horizontal position 

 this greatly reduces the unsteadiness to which this 

 form of foot, as we have before remarked, is liable. 



Messrs. Swift and Son, of Tottenham Court Road, 



"11^4_J 



Swift "Histological."' 



make a microscope which they call their " Histo- 

 logical and Physiological Microscope." The stand is 

 a firm tripod, there is coarse adjustment by rack and 

 pinion, direct-acting tine adjustment, draw-tube, 

 mirrors, stage with horse-shoe opening, and fitting 

 beneath of the standard size for illuminating apparatus. 

 With one eye-piece, inch and J inch objectives, Abbe 

 condenser with iris diaphragm, and case complete, the 

 price is £S 17s., or with sliding coarse adjustment, 

 30 shillings less. A proper focussing and centering 

 sub-stage costs 38 shillings more. An exactly similar 

 microscope on four legs, giving exceptional steadiness, 

 costs 5 shillings more. 



(To hi continued. ) 



