February 24, 1888.] 



SCIENCE. 



97 



The Nutriment in Edible Fungi. 



It is a favorite theory with some that the nutritive value of many 

 of the fungi that are used as food is almost equal to the nutritive 

 value of meat. A recent statement by the eminent chemist of Ger- 

 many, Mr. C. T. Morner, is to the effect that the total nitrogen in 

 this class of fungi varies between 2 and 3.64 per cent in the dry 

 material ; that 41 per cent of the total nitrogen is useful in ali- 

 mentation ; that all the rest belongs to non-assimilable bodies ; and 

 that, notwithstanding the relatively high figures, fungi constitute a 

 very mediocre food, since the figures relate to dry material, and 

 fungi contain enormous quantities of water. Mr. Morner, in this 

 connection, gives a number of tables which show the amount of the 

 several fungi that would be required to equal a pound of beef : 

 mushrooms, 9 pounds ; Lactarius delictosus, 24 pounds ; chanter- 

 elle, 41 pounds ; morel, 15 pounds; Polyporiis ovinits, 67 pounds. 



Some recent experiments at the agricultural e.xperiment station 

 of the State of New York do not appear to sustain the statements 

 of Professor Morner. A quantity of mushrooms {Agaricus cam- 

 pestris) growing in a pasture was gathered and subjected to an 

 analysis, and the digestibility of the albuminoids determined by the 

 pepsin method. The results were as follows : — 



Water 



Ash 



Albuminoids. 

 Crude fibre . . 

 Nitrogen-free 

 Fat (eth. 



Total nitrogen 



Albuminoids digested.. 



56.00 

 7.0S 



21.83 

 7.32 



8.g6 

 84.50 



The total nitrogen found in the dry substance was about 2.5 

 times as great as the highest figures given by the German chemist, 

 while the digestibility placed it among the exceptionally rich nitro- 

 genous foods. Experiments were also made with puff-balls. A 

 very large one was found to have been broken into many fragments 

 by careless handling. Many of the broken fragments were gathered 

 together and taken for analysis. This specimen was in fine edible 

 maturity. Another fresh one, a fine large specimen of Lycoperdon 

 gigaiiteum, was examined. The following measurements were 

 taken in connection with the analysis: greatest diameter, 12.5 

 inches ; height, 7.5 inches ; horizontal circumference, 37.25 inches ; 

 vertical circumference, 33.5 inches; weight, 2,864 grams, or 6.35 

 pounds. The puff-ball was kept until the following morning be- 

 fore examination, when it was found to have lost 5.93 per cent by 

 weight. A slice from the centre was taken for analysis. This 

 contained 92.18 per cent of water. In the following table. No. i 

 refers to the whole puff-ball, which was larger and more mature 

 than No. 2, the broken one. 





No. I. 



No. 2. 





Fresh 

 Substance. 



Water 

 Free. 



Water 

 Free. 



Water 



Ash 



Albuminoids 



92.18 

 ■58 



519 

 .8q 



I. OS 



7-47 

 66.34 

 11.42 

 13-33 



1.44 



6.97 

 57-44 





22.05 

 2.47 







Total nitrogen 





10.63 9-19 

 70 04 81.72 







The total nitrogen for one of the puff-palls was about three times 



as great as the highest figures by Morner ; and, even with the large 

 percentage of water, it compares favorable in nutritive value with 

 meat. It would seem, from the analyses which were made at the 

 station, that Morner's specimens must have been very poor ones, 

 or else the fungi in Germany are not so rich in albuminoids as those 

 growing wild in the State of New York. 



Frederic G. Mather. 



Albany, N.Y., Feb. 14. 



A Worm in a Hen's Egg. 



On Sunday, Feb. 12, 1888, a lady in this city, on opening the egg; 

 of an ordinary hen, observed a worm lying coiled in the albumen or 

 ' white ' of the egg, near the lesser or pointed end. She placed the- 

 egg in a saucer, and the albumen flowed out through the opening 

 in the shell, carrying the worm with it. After exhibiting to friends 

 during the day, it was brought to me, Feb. 12. Upon examination, 

 I find it to be an Ascaris lumbricoides about four inches in length ;. 

 and, with the statement verified, the phenomenon becomes interest- 

 ing in many ways. G. C. Ashmun. 



Cleveland, O., Feb. 14. 



Self-Recording Rain-Gauge. 



This recording mechanism is designed to be attached directlv to- 

 the Signal Service standard gauge, now in such general use at all 

 regular stations, and also at nearly all volunteer stations. 



The figure is a sectional elevation of the gauge with the record- 

 ing devices in position. The rain is received in the cylindrical part 

 R, and is conducted by means of the funnel-shaped bottom into- 

 the inner tube or tall cylinder, which is made of drawn brass tubing, 

 accurately sized, so that its sectional area is just one-tenth that of 

 the receiver R, thus magnifying the rainfall tenfold. R is made 

 eight inches in diameter, and the brass tube is twenty inches high, 

 and holds two inches of rainfall, any in excess of this quantity over- 

 flowing into the outer cylinder, where it is retained and subsequently 

 measured. 



The recording mechanism needs little explanation. Definite, 

 positive rotation of the dial-wheel in response to movements of the 

 float is secured by use of the sprocket wheel and chain. A few ' 

 links of the latter in enlarged view are shown on the left. The 

 sprocket-wheel is graduated into divisions, each corresponding to a 

 hundredth of an inch of rainfall. At intervals of every five divisions 

 the wheel is set with small pins, which, when the wheel revolves,, 

 successively deflect a feeble spring, and momentarily close an electric 

 circuit, thus recording successive five-hundredths of an inch of rain- 

 fall. The record is made in precisely the same manner as that in 

 which the wind-velocity is now recorded at all signal service sta- 

 tions. Wires from the rain-gauge lead to a battery and an electro- 

 magnet which operates an armature provided with a pen or pencil 

 that traces a line on a sheet of paper wound on a cylinder slowly 

 revolved by clock-work. When the electric circuit is closed, the 

 pen is drawn aside, and makes a small notch in the fine, each notch 

 representing five-hundredths of an inch of rainfall. 



Although the chain is quite light, weighing but a few grams per 

 foot, yet its weight cannot be neglected, modifying, as it does, the 

 conditions of equilibrium between the float and counterpoise. Thus, 

 imagine the gauge to be empty, and the float resting on the bottom. 

 It is evident that a certain quantity of water must be added before 

 the float will begin to be lifted on the water. This condition is in- 

 dicated in the figure by the dotted lines, and with the height of the 

 water marked h^. In order to properly include in the measurement 

 this quantity of water, which must be added before the float just 

 begins to be lifted, the graduated disk, which for this purpose is- 

 made adjustable on the sprocket-wheel, is set, not with its zero-line 

 to the inde.x-point, but with some other line, — a line corresponding 

 in its value to the quantity of water required to just support the 

 float when at the bottom of the gauge. Allowance is thus made 

 once for all, and the graduated disk, with its pins, firmly and finally 

 attached to the body of the wheel. Now, as more water is added, 

 the float rises. But it is observed, that, as the chain passes over 

 the wheel, its weight is not only added to that on the counterpoise 

 side, but is also subtracted from that on the float side ; so that the 

 equilibrium is, on the one hand, disturbed by twice the weight of 

 the chain passing overthe wheel, and, on the other hand, is restored 

 by the rise of the float itself in the water. It follows, therefore. 



